DTLK / Datalink Corp. - SEC Filings, Annual Report, Proxy Statement

Datalink Corp.
US ˙ NASDAQ
THIS SYMBOL IS NO LONGER ACTIVE

Basic Stats
CIK 1056923
SEC Filings
All companies that sell securities in the United States must register with the Securities and Exchange Commission (SEC) and file reports on a regular basis. These reports include company annual reports (10K, 10Q), news updates (8K), investor presentations (found in 8Ks), insider trades (form 4), ownership reports (13D, and 13G), and reports related to the specific securities sold, such as registration statements and prospectus. This page shows recent SEC filings related to Datalink Corp.
SEC Filings (Chronological Order)
This page provides a complete, chronological list of SEC Filings, excluding ownership filings which we provide elsewhere.
February 9, 2018 SC 13G/A

DTLK / Datalink Corp. / DIMENSIONAL FUND ADVISORS LP - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 dfs655.htm SCHEDULE 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* DATALINK CORP (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2017 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the

February 9, 2017 SC 13G

DTLK / Datalink Corp. / DIMENSIONAL FUND ADVISORS LP - SCHEDULE 13G Passive Investment

SC 13G 1 dfs205.htm SCHEDULE 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* DATALINK CORP (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2016 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule

February 9, 2017 SC 13G/A

DTLK / Datalink Corp. / Wellington Trust Co NA - SEC SCHEDULE 13G Passive Investment

SC 13G/A 1 SEC13GFiling.htm SEC SCHEDULE 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2 )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 30, 2016 (Date of Event Which Requires Filing of this Statement) Check the appropriate box t

February 9, 2017 SC 13G/A

DTLK / Datalink Corp. / Wellington Trust Company, National Association Multiple Common Trust Funds Trust, Micro Cap Equity Portfolio - SEC SCHEDULE 13G Passive Investment

SC 13G/A 1 SEC13GFiling.htm SEC SCHEDULE 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1 )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 30, 2016 (Date of Event Which Requires Filing of this Statement) Check the appropriate box t

January 18, 2017 15-12G

Datalink 15-12G

15-12G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. Commission File Number: 000-29758 Datalink Corporation (Exact name of registrant as specifie

January 6, 2017 S-8 POS

Datalink S-8 POS

S-8 POS As filed with the Securities and Exchange Commission on January 6, 2017 Registration No.

January 6, 2017 S-8 POS

Datalink S-8 POS

S-8 POS As filed with the Securities and Exchange Commission on January 6, 2017 Registration No.

January 6, 2017 S-8 POS

Datalink S-8 POS

S-8 POS As filed with the Securities and Exchange Commission on January 6, 2017 Registration No.

January 6, 2017 S-8 POS

Datalink S-8 POS

S-8 POS 1 d296744ds8pos.htm S-8 POS As filed with the Securities and Exchange Commission on January 6, 2017 Registration No. 333-93229 Registration No. 333-166885 Registration No. 333-175593 Registration No. 333-182653 Registration No. 333-206370 Registration No. 333-211809 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 REGISTRATION

January 6, 2017 S-8 POS

Datalink S-8 POS

S-8 POS 1 d296744ds8pos.htm S-8 POS As filed with the Securities and Exchange Commission on January 6, 2017 Registration No. 333-93229 Registration No. 333-166885 Registration No. 333-175593 Registration No. 333-182653 Registration No. 333-206370 Registration No. 333-211809 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 REGISTRATION

January 6, 2017 S-8 POS

Datalink S-8 POS

S-8 POS 1 d296744ds8pos.htm S-8 POS As filed with the Securities and Exchange Commission on January 6, 2017 Registration No. 333-93229 Registration No. 333-166885 Registration No. 333-175593 Registration No. 333-182653 Registration No. 333-206370 Registration No. 333-211809 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 REGISTRATION

January 6, 2017 POS AM

Datalink POS AM

As filed with the Securities and Exchange Commission on January 6, 2017 Registration No.

January 6, 2017 POS AM

Datalink POS AM

POS AM As filed with the Securities and Exchange Commission on January 6, 2017 Registration No.

January 6, 2017 POS AM

Datalink POS AM

As filed with the Securities and Exchange Commission on January 6, 2017 Registration No.

January 6, 2017 EX-3.1

AMENDED AND RESTATED ARTICLES OF INCORPORATION OF DATALINK CORPORATION

EX-3.1 2 a17-12951ex3d1.htm EX-3.1 Exhibit 3.1 AMENDED AND RESTATED ARTICLES OF INCORPORATION OF DATALINK CORPORATION 1. Name. The name of the corporation is Datalink Corporation. 2. Registered Office and Registered Agent. The address of the registered office of the corporation in Minnesota is 100 South 5th Street, Suite 1075, Minneapolis, Minnesota 55402. The registered agent of the corporation a

January 6, 2017 8-K

Changes in Control of Registrant, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Material Modification to Rights of Security Holders, Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing, Financial Statements and Exhibits, Completion of Acquisition or Disposition of Assets

8-K 1 a17-129518k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 January 6, 2017 Date of report (Date of earliest event reported) DATALINK CORPORATION (Exact Name of Registrant as Specified in its Charter) Minnesota 000-29758 41-0856543 (State of Incorporation) (Commissio

January 6, 2017 EX-3.2

DATALINK CORPORATION AS ADOPTED BY THE BOARD OF DIRECTORS November 6, 2016

EX-3.2 3 a17-12951ex3d2.htm EX-3.2 Exhibit 3.2 BYLAWS OF DATALINK CORPORATION AS ADOPTED BY THE BOARD OF DIRECTORS ON November 6, 2016 Table of Contents Page Article 1. Shareholder Meetings 1 1.1 Place of Meetings 1 1.2 Regular Meetings 1 1.3 Special Meetings 1 1.4 Quorum, Adjourned Meetings 1 1.5 Voting 1 1.6 Record Date 1 1.7 Notice of Meetings 2 1.8 Written Action 2 1.9 Chief Executive Officer;

January 6, 2017 SC 13D/A

DTLK / Datalink Corp. / INSIGHT ENTERPRISES INC - SC 13D AMENDMENT NO. 1 Activist Investment

SC 13D/A 1 d328083dsc13da.htm SC 13D AMENDMENT NO. 1 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D (AMENDMENT NO. 1) Under the Securities Exchange Act of 1934 Datalink Corporation (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 237934104 (CUSIP Number) Samuel C. Cowley Insight Enterprises, Inc. 6820 South Harl Avenue T

January 5, 2017 8-K

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 January 5, 2017 Date of report (Date of earliest event reported) DATALINK CORPORATION (Exact Name of Registrant as Specified in its Charter) Minnesota 000-29758 41-0856543 (State of Incorporation) (Commission File Number) (I.R.S. Emp

December 23, 2016 DEFA14A

Datalink DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ? Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) o Defin

December 16, 2016 DEFA14A

Datalink DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14A-101) Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6

December 12, 2016 SC 13G/A

DTLK / Datalink Corp. / Wellington Management Group LLP - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 6 )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) November 30, 2016 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this S

November 30, 2016 DFAN14A

Datalink DFAN14A

DFAN14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Pro

November 30, 2016 SC 13D

DTLK / Datalink Corp. / Sand Grove Capital Management LLP - DATALINK CORPORATION SC 13D Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. )* DATALINK CORPORATION (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) Penelope Brudenell-Bruce 4th floor, 35 Dover Street London W1S 4NQ +44 (0) 203 770 8614 (Name, Address and Telephone Number of Person Authorized to

November 29, 2016 DEFA14A

Datalink DEFA14A

DEFA14A 1 a16-218173defa14a.htm DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14A-101) Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Com

November 29, 2016 DEFM14A

Datalink DEFM14A

Use these links to rapidly review the document TABLE OF CONTENTS TABLE OF CONTENTS Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

November 18, 2016 PREM14A

Datalink PREM14A

Use these links to rapidly review the document TABLE OF CONTENTS TABLE OF CONTENTS Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

November 17, 2016 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Entry into a Material Definitive Agreement, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 November 16, 2016 Date of report (Date of earliest event reported) DATALINK CORPORATION (Exact Name of Registrant as Specified in its Charter) Minnesota 000-29758 41-0856543 (State of Incorporation) (Commission File Number) (I.R.S. E

November 17, 2016 EX-10.2

November 16, 2016

EX-10.2 3 a16-218461ex10d2.htm EX-10.2 Exhibit 10.2 November 16, 2016 Denise Westenfield 6400 Craig Drive Eden Prairie, MN 55346 Re: Retention Bonus Agreement Dear Denise: As you are aware, Datalink Corporation, a Minnesota corporation (“Datalink”), has entered into an Agreement and Plan of Merger with Insight Enterprises, Inc., a Delaware corporation (“Insight”), and certain other parties (the “M

November 17, 2016 EX-10.1

NOVEMBER 16, 2016

EX-10.1 2 a16-218461ex10d1.htm EX-10.1 Exhibit 10.1 NOVEMBER 16, 2016 PAUL F. LIDSKY 18715 — 24TH AVENUE NORTH PLYMOUTH, MINNESOTA 55447 Re: Retention Bonus and Consulting Agreement Dear Paul: As you are aware, Datalink Corporation, a Minnesota corporation (“Datalink”), has entered into an Agreement and Plan of Merger with Insight Enterprises, Inc., a Delaware corporation (“Insight”), and certain

November 14, 2016 DEFA14A

Datalink DEFA14A

DEFA14A 1 a16-212273defa14a.htm DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14A-101) Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Com

November 14, 2016 SC 13D

DTLK / Datalink Corp. / INSIGHT ENTERPRISES INC - SC 13D Activist Investment

SC 13D UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 Datalink Corporation (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 237934104 (CUSIP Number) Samuel C. Cowley Insight Enterprises, Inc. 6820 South Harl Avenue Tempe, Arizona 85283 (480) 333-3000 (Name, Address and Telephone

November 9, 2016 EX-10.1

FOURTH AMENDMENT TO CREDIT AGREEMENT AND WAIVER

EX-10.1 2 a16-171181ex10d1.htm EX-10.1 Exhibit 10.1 FOURTH AMENDMENT TO CREDIT AGREEMENT AND WAIVER This FOURTH AMENDMENT TO CREDIT AGREEMENT AND WAIVER (“Amendment”), is made effective as of October 31, 2016 (the “Fourth Amendment Date”), by and between DATALINK CORPORATION, a Minnesota corporation, having its chief executive office located at 10050 Crosstown Circle, Suite 500, Eden Prairie, Minn

November 9, 2016 10-Q

Datalink 10-Q (Quarterly Report)

10-Q 1 a16-17118110q.htm 10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: September 30, 2016 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition perio

November 7, 2016 EX-99.1

THOMSON REUTERS STREETEVENTS | www.streetevents.com | Contact Us ©2016 Thomson Reuters. All rights reserved. Republication or redistribution of Thomson Reuters content, including by framing or similar means, is prohibited without the prior written co

EX-99.1 2 d269216dex991.htm EX-99.1 Exhibit 99.1 Rule 14a-12 Legends Cautionary Note Regarding Forward-Looking Statements Certain statements contained in this communication may constitute “forward-looking statements.” Forward-looking statements can usually be identified by the use of words such as “aim,” “anticipate,” “believe,” “continue,” “could,” “estimate,” “evolve,” “expect,” “forecast,” “int

November 7, 2016 EX-99.2

Response

EX-99.2 Exhibit 99.2 External Media and Social Responses/Messaging Event Response Spokesperson/Attribution Media Inquiry This merger will bring Insight?s 6000 global teammates together with Datalink?s 575. The intention is to leverage Datalink?s highly successful enterprise data center solutions platform, and strong Professional, Consulting, Managed and One Call? support services, all of which are

November 7, 2016 DFAN14A

Datalink DFAN14A

DFAN14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Pro

November 7, 2016 EX-99.1

Insight’s Acquisition of Datalink Insight to acquire Datalink (Nasdaq: “DTLK”) for $11.25 per share, implying an equity value of approximately $258 million and transaction value of $196 million (net of cash and debt acquired) Strengthens position as

EX-99.1 2 d286405dex991.htm EX-99.1 A Special Insight Announcement November 2016 Insight All-Hands Exhibit 99.1 Insight’s Acquisition of Datalink Insight to acquire Datalink (Nasdaq: “DTLK”) for $11.25 per share, implying an equity value of approximately $258 million and transaction value of $196 million (net of cash and debt acquired) Strengthens position as a market leading IT solutions provider

November 7, 2016 EX-99.3

Insight’s Acquisition of Datalink Insight to acquire Datalink (Nasdaq: “DTLK”) for $11.25 per share, implying an equity value of approximately $258 million and transaction value of $196 million (net of cash and debt acquired) Strengthens position as

EX-99.3 A Special Insight Announcement November 7, 2016 INALT Exhibit 99.3 Insight’s Acquisition of Datalink Insight to acquire Datalink (Nasdaq: “DTLK”) for $11.25 per share, implying an equity value of approximately $258 million and transaction value of $196 million (net of cash and debt acquired) Strengthens position as a market leading IT solutions provider with global scale and deep technical

November 7, 2016 EX-99.2

Insight’s Acquisition of Datalink Insight to acquire Datalink (Nasdaq: “DTLK”) for $11.25 per share, implying an equity value of approximately $258 million and transaction value of $196 million (net of cash and debt acquired) Strengthens position as

EX-99.2 A Special Announcement November 7, 2016 Datalink All-Hands Exhibit 99.2 Insight?s Acquisition of Datalink Insight to acquire Datalink (Nasdaq: ?DTLK?) for $11.25 per share, implying an equity value of approximately $258 million and transaction value of $196 million (net of cash and debt acquired) Strengthens position as a market leading IT solutions provider with global scale and deep tech

November 7, 2016 DFAN14A

Datalink DFAN14A

DFAN14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Pro

November 7, 2016 DFAN14A

Datalink DFAN14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ☐ Filed by a party other than the Registrant ☒ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

November 7, 2016 DEFA14A

Datalink DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14A-101) Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6

November 7, 2016 DEFA14A

Datalink DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14A-101) Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6

November 7, 2016 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 November 7, 2016 (Date of Report ? date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 000-29758 41-0856543 (Commission File No.

November 7, 2016 EX-99.1

DATALINK REPORTS 2016 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Cancels Conference Call This Afternoon

Exhibit 99.1 DATALINK REPORTS 2016 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Cancels Conference Call This Afternoon EDEN PRAIRIE, Minn., November 7, 2016 ? Datalink (Nasdaq: DTLK), a leading provider of IT services and solutions, today reported results for its third quarter and nine months that ended September 30, 2016. Revenues for the quarter ended September 30, 2016, decreased 7% to $184.0

November 7, 2016 EX-99.1

VOTING AGREEMENT

EX-99.1 Exhibit 99.1 VOTING AGREEMENT VOTING AGREEMENT, dated as of November 6, 2016 (this ?Agreement?), by and among Insight Enterprises, Inc., a Delaware corporation (?Parent?), Datalink Corporation, a Minnesota corporation (the ?Company?), and the undersigned holders (the ?Shareholders? and each, a ?Shareholder?) of capital stock of the Company. Capitalized terms used but not otherwise defined

November 7, 2016 EX-99.2

Insight Enterprises to Acquire Datalink

EX-99.2 Exhibit 99.2 NASDAQ: NSIT, DTLK Insight Enterprises to Acquire Datalink TEMPE, Ariz. and Eden Prairie, Minn., November 7, 2016 ? Insight Enterprises (Nasdaq:NSIT), an Intelligent Technology Solutions? provider (?Insight? or ?the Company?), and Datalink Corporation (Nasdaq:DTLK), a leading provider of IT services and enterprise data center solutions (?Datalink?), have entered into a definit

November 7, 2016 DFAN14A

Datalink 8-K

DFAN14A 1 d194915d8k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) November 6, 2016 Insight Enterprises, Inc. (Exact name of registrant as specified in its charter) Delaware 0-25092 86-0766246 (State of Incorporation) (Com

November 7, 2016 EX-2.1

AGREEMENT AND PLAN OF MERGER INSIGHT ENTERPRISES, INC. REEF ACQUISITION CO. (“Merger Sub”) DATALINK CORPORATION (the “Company”) Dated as of November 6, 2016 TABLE OF CONTENTS Article 1 THE MERGER 2 Section 1.1 The Merger 2 Section 1.2 Merger Closing

EX-2.1 Exhibit 2.1 AGREEMENT AND PLAN OF MERGER among INSIGHT ENTERPRISES, INC. (?Parent?), REEF ACQUISITION CO. (?Merger Sub?) and DATALINK CORPORATION (the ?Company?) Dated as of November 6, 2016 TABLE OF CONTENTS Article 1 THE MERGER 2 Section 1.1 The Merger 2 Section 1.2 Merger Closing 2 Section 1.3 Effect of Merger; Organizational Documents; Directors and Officers 2 Section 1.4 Conversion of

November 7, 2016 EX-99.3

Important Information Cautionary Note Regarding Forward-Looking Statements Certain statements contained in this communication may constitute “forward-looking statements.” Forward-looking statements can usually be identified by the use of words such a

EX-99.3 Insight to Acquire Datalink November 7, 2016 Exhibit 99.3 Important Information Cautionary Note Regarding Forward-Looking Statements Certain statements contained in this communication may constitute ?forward-looking statements.? Forward-looking statements can usually be identified by the use of words such as ?aim,? ?anticipate,? ?believe,? ?continue,? ?could,? ?estimate,? ?evolve,? ?expect

November 7, 2016 EX-2.1

AGREEMENT AND PLAN OF MERGER INSIGHT ENTERPRISES, INC. (“Parent”), REEF ACQUISITION CO. (“Merger Sub”) DATALINK CORPORATION (the “Company”) Dated as of November 6, 2016

Exhibit 2.1 AGREEMENT AND PLAN OF MERGER among INSIGHT ENTERPRISES, INC. (?Parent?), REEF ACQUISITION CO. (?Merger Sub?) and DATALINK CORPORATION (the ?Company?) Dated as of November 6, 2016 TABLE OF CONTENTS Article 1 THE MERGER 2 Section 1.1 The Merger 2 Section 1.2 Merger Closing 2 Section 1.3 Effect of Merger; Organizational Documents; Directors and Officers 2 Section 1.4 Conversion of Merger

November 7, 2016 EX-99.1

Insight Enterprises to Acquire Datalink

Exhibit 99.1 NASDAQ: NSIT, DTLK Insight Enterprises to Acquire Datalink TEMPE, Ariz. and Eden Prairie, Minn., November 7, 2016 ? Insight Enterprises (Nasdaq:NSIT), an Intelligent Technology Solutions? provider (?Insight? or ?the Company?), and Datalink Corporation (Nasdaq:DTLK), a leading provider of IT services and enterprise data center solutions (?Datalink?), have entered into a definitive merg

November 7, 2016 EX-3.1

AMENDED AND RESTATED BY-LAWS of DATALINK CORPORATION Adopted November 6, 2016

Exhibit 3.1 AMENDED AND RESTATED BY-LAWS of DATALINK CORPORATION Adopted November 6, 2016 SHAREHOLDERS Section 1.01 PLACE OF MEETINGS. Each meeting of the shareholders shall be held at the principal executive office of the Corporation or at such other place as may be designated by the Board of Directors or the Chief Executive Officer. But any meeting called by or at the demand of a shareholder or

November 7, 2016 8-K

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Entry into a Material Definitive Agreement, Financial Statements and Exhibits

8-K 1 a16-2118818k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 November 6, 2016 Date of report (Date of earliest event reported) DATALINK CORPORATION (Exact Name of Registrant as Specified in its Charter) Minnesota 000-29758 41-0856543 (State of Incorporation) (Commiss

November 7, 2016 EX-10.2

[FORM OF] AMENDED AND RESTATED INDEMNIFICATION AGREEMENT

Exhibit 10.2 [FORM OF] AMENDED AND RESTATED INDEMNIFICATION AGREEMENT THIS AMENDED AND RESTATED INDEMNIFICATION AGREEMENT is made effective as of November 6, 2016, by and between DATALINK CORPORATION, a Minnesota corporation (the ?Company?), and (?Indemnitee?). WHEREAS, it is essential to the Company to retain and attract as directors the most capable persons available; WHEREAS, Indemnitee continu

November 7, 2016 DEFA14A

Datalink 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 November 6, 2016 Date of report (Date of earliest event reported) DATALINK CORPORATION (Exact Name of Registrant as Specified in its Charter) Minnesota 000-29758 41-0856543 (State of Incorporation) (Commission File Number) (I.R.S. Em

November 7, 2016 EX-99.1

Insight Enterprises to Acquire Datalink

Exhibit 99.1 NASDAQ: NSIT, DTLK Insight Enterprises to Acquire Datalink TEMPE, Ariz. and Eden Prairie, Minn., November 7, 2016 — Insight Enterprises (Nasdaq:NSIT), an Intelligent Technology Solutions™ provider (“Insight” or “the Company”), and Datalink Corporation (Nasdaq:DTLK), a leading provider of IT services and enterprise data center solutions (“Datalink”), have entered into a definitive merg

November 7, 2016 EX-2.1

AGREEMENT AND PLAN OF MERGER INSIGHT ENTERPRISES, INC. (“Parent”), REEF ACQUISITION CO. (“Merger Sub”) DATALINK CORPORATION (the “Company”) Dated as of November 6, 2016

Exhibit 2.1 AGREEMENT AND PLAN OF MERGER among INSIGHT ENTERPRISES, INC. (?Parent?), REEF ACQUISITION CO. (?Merger Sub?) and DATALINK CORPORATION (the ?Company?) Dated as of November 6, 2016 TABLE OF CONTENTS Article 1 THE MERGER 2 Section 1.1 The Merger 2 Section 1.2 Merger Closing 2 Section 1.3 Effect of Merger; Organizational Documents; Directors and Officers 2 Section 1.4 Conversion of Merger

November 7, 2016 EX-10.2

[FORM OF] AMENDED AND RESTATED INDEMNIFICATION AGREEMENT

Exhibit 10.2 [FORM OF] AMENDED AND RESTATED INDEMNIFICATION AGREEMENT THIS AMENDED AND RESTATED INDEMNIFICATION AGREEMENT is made effective as of November 6, 2016, by and between DATALINK CORPORATION, a Minnesota corporation (the ?Company?), and (?Indemnitee?). WHEREAS, it is essential to the Company to retain and attract as directors the most capable persons available; WHEREAS, Indemnitee continu

November 7, 2016 EX-3.1

AMENDED AND RESTATED BY-LAWS of DATALINK CORPORATION Adopted November 6, 2016

EX-3.1 3 a16-211881ex3d1.htm AMENDED AND RESTATED BY-LAWS ADOPTED NOVEMBER 6, 2016 Exhibit 3.1 AMENDED AND RESTATED BY-LAWS of DATALINK CORPORATION Adopted November 6, 2016 SHAREHOLDERS Section 1.01 PLACE OF MEETINGS. Each meeting of the shareholders shall be held at the principal executive office of the Corporation or at such other place as may be designated by the Board of Directors or the Chief

August 5, 2016 10-Q

Datalink 10-Q (Quarterly Report)

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: June 30, 2016 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission file number: 0

July 28, 2016 EX-99.1

10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK REPORTS 2016 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 9% and 2% Year-Over-Year, Respectively Second Quarter and Six Month Earnings from

EX-99.1 2 a16-157311ex99d1.htm EX-99.1 Exhibit 99.1 10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK REPORTS 2016 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 9% and 2% Year-Over-Year, Respectively Second Quarter and Six Month Earnings from Operations Up 212% and 182% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., July 28, 2016 — Data

July 28, 2016 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K 1 a16-1573118k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 July 28, 2016 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization

June 3, 2016 S-8

Datalink S-8

As filed with the Securities and Exchange Commission on June 3, 2016. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 DATALINK CORPORATION (Exact Name of Registrant as Specified in Its Charter) Minnesota (State or Other Jurisdiction of Incorporation or Organization) 41-0856543 (I.R.S. Emp

May 26, 2016 8-K

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 25, 2016 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

May 10, 2016 10-Q

Datalink 10-Q (Quarterly Report)

10-Q 1 a16-6568110q.htm 10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: March 31, 2016 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period fro

May 10, 2016 EX-10.1

THIRD AMENDMENT TO CREDIT AGREEMENT

EX-10.1 2 a16-65681ex10d1.htm EX-10.1 Exhibit 10.1 THIRD AMENDMENT TO CREDIT AGREEMENT This THIRD AMENDMENT TO CREDIT AGREEMENT (“Amendment”), is made effective as of April 22, 2016 (the “Third Amendment Date”), by and between DATALINK CORPORATION, a Minnesota corporation, having its chief executive office located at 10050 Crosstown Circle, Suite 500, Eden Prairie, Minnesota 55344 (“Borrower), and

April 27, 2016 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 April 27, 2016 (Date of Report ? date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 000-29758 41-0856543 (Commission File No.

April 27, 2016 EX-99.1

DATALINK REPORTS FIRST QUARTER 2016 OPERATING RESULTS Revenues Affected by Late Orders & Shipments; Flash Storage & Services Sales Continue to Increase

Exhibit 99.1 DATALINK REPORTS FIRST QUARTER 2016 OPERATING RESULTS Revenues Affected by Late Orders & Shipments; Flash Storage & Services Sales Continue to Increase EDEN PRAIRIE, Minn., April 27, 2016 ? Datalink (Nasdaq: DTLK), a leading provider of IT services and solutions, today reported first quarter 2016 financial results. Revenues for the quarter ended March 31, 2016, declined 6% to $164.6 m

April 15, 2016 DEFA14A

Datalink DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) o Defin

April 15, 2016 DEF 14A

Datalink DEF 14A

QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

March 24, 2016 SC 13G

DTLK / Datalink Corp. / Wellington Trust Company, National Association Multiple Common Trust Funds Trust, Micro Cap Equity Portfolio - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) March 15, 2016 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedu

March 14, 2016 10-K

Datalink 10-K (Annual Report)

QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

March 14, 2016 EX-10.22

DATALINK CORPORATION Performance Stock Unit Award Agreement Under the 2011 Incentive Compensation Plan

Exhibit 10.22 DATALINK CORPORATION Performance Stock Unit Award Agreement Under the 2011 Incentive Compensation Plan Datalink Corporation (the “Company”), pursuant to its 2011 Incentive Compensation Plan (the “Plan”), hereby grants to you, the Grantee named below, an award of Performance Stock Units (“Units”) involving the number of Units set forth in the table below. The terms and conditions of t

February 24, 2016 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K 1 a16-522518k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 February 24, 2016 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organizat

February 24, 2016 EX-99.1

10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK REPORTS 2015 FOURTH QUARTER AND TWELVE MONTH OPERATING RESULTS Fourth Quarter and Twelve Month Revenues Up 12% and 21% Year-Over-Year, Respectively; Professional Services Revenues Inc

Exhibit 99.1 10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK REPORTS 2015 FOURTH QUARTER AND TWELVE MONTH OPERATING RESULTS Fourth Quarter and Twelve Month Revenues Up 12% and 21% Year-Over-Year, Respectively; Professional Services Revenues Increased 28% to 9% of Total Revenues in 2015 EDEN PRAIRIE, Minn., February 24, 2016 ? Datalink (Nasdaq: DTLK), a leading provider of IT ser

February 11, 2016 SC 13G/A

DTLK / Datalink Corp. / Wellington Management Group LLP - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 5 )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2015 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this S

February 11, 2016 SC 13G/A

DTLK / Datalink Corp. / Wellington Trust Co NA - SEC SCHEDULE 13G Passive Investment

SC 13G/A 1 SEC13GFiling.htm SEC SCHEDULE 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1 )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2015 (Date of Event Which Requires Filing of this Statement) Check the appropriate box t

February 9, 2016 SC 13G

Datalink SCHEDULE 13G (Passive Acquisition of More Than 5% of Shares)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* DATALINK CORP (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2015 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule i

November 6, 2015 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: September 30, 2015 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission file numb

October 21, 2015 EX-99.1

DATALINK REPORTS 2015 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Third Quarter and Nine Month Revenues Up 37% and 25% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2015 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Third Quarter and Nine Month Revenues Up 37% and 25% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., October 21, 2015 ? Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its third quarter and nine months that ended September 30, 2015. Financial result

October 21, 2015 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K 1 a15-2149118k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 October 21, 2015 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organizat

September 14, 2015 EX-99.1

10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK ANNOUNCES SHARE REPURCHASE PROGRAM

Exhibit 99.1 10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK ANNOUNCES SHARE REPURCHASE PROGRAM EDEN PRAIRIE, Minn., September 14, 2015 ? Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today announced that its board of directors has approved a share repurchase program authorizing the repurchase of shares of its common stock in the open ma

September 14, 2015 8-K

Datalink 8-K (Current Report/Significant Event)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 14, 2015 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization

August 14, 2015 S-8

Datalink S-8

S-8 1 a15-176221s8.htm S-8 As filed with the Securities and Exchange Commission on August 14, 2015. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 DATALINK CORPORATION (Exact Name of Registrant as Specified in Its Charter) Minnesota (State or Other Jurisdiction of Incorporation or Organi

August 7, 2015 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: June 30, 2015 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission file number: 0

July 30, 2015 EX-99.1

DATALINK REPORTS 2015 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 15% and 20% Year-Over-Year, Respectively

EX-99.1 2 a15-166341ex99d1.htm EX-99.1 Exhibit 99.1 DATALINK REPORTS 2015 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 15% and 20% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., July 30, 2015 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its second quarter and six months that ended

July 30, 2015 8-K

Datalink 8-K (Current Report/Significant Event)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 July 30, 2015 (Date of Report ? date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

May 22, 2015 EX-10.1

SECOND AMENDMENT TO CREDIT AGREEMENT

Exhibit 10.1 SECOND AMENDMENT TO CREDIT AGREEMENT This SECOND AMENDMENT TO CREDIT AGREEMENT (“Amendment”), is made effective as of May 21, 2015 (the “Second Amendment Date”), by and between DATALINK CORPORATION, a Minnesota corporation, having its chief executive office located at 10050 Crosstown Circle, Suite 500, Eden Prairie, Minnesota 55344 (“Borrower”), and CASTLE PINES CAPITAL LLC, a Delawar

May 22, 2015 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

8-K 1 a15-1264218k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 21, 2015 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporat

May 21, 2015 8-K

Submission of Matters to a Vote of Security Holders

8-K 1 a15-1252418k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 20, 2015 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporat

May 8, 2015 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: March 31, 2015 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission file number:

May 5, 2015 EX-99.1

DATALINK REPORTS 2015 FIRST QUARTER OPERATING RESULTS First-Quarter Revenues Up 26% Year-Over-Year, Including 28% Increase in Professional Services Revenues

EX-99.1 2 a15-108481ex99d1.htm EX-99.1 Exhibit 99.1 DATALINK REPORTS 2015 FIRST QUARTER OPERATING RESULTS First-Quarter Revenues Up 26% Year-Over-Year, Including 28% Increase in Professional Services Revenues EDEN PRAIRIE, Minn., May 5, 2015 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its first quarter ended March 31, 2015. F

May 5, 2015 8-K

Datalink 8-K (Current Report/Significant Event)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 May 5, 2015 (Date of Report ? date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

April 7, 2015 DEF 14A

Datalink DEF 14A

QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

April 7, 2015 EX-99.1

2014

Exhibit 99.1 Letter to Our Shareholders DEAR SHAREHOLDERS: In the data center market, what sets the most successful companies apart is their ability to help customers seamlessly navigate every phase of the IT lifecycle in the face of a complex and rapidly changing technology landscape. The top companies are full-service providers that do more than simply take orders. They enable. They problem-solv

April 7, 2015 8-K

Datalink 8-K (Current Report/Significant Event)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 April 7, 2015 (Date of Report ? date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

March 13, 2015 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 10-K

10-K 1 a2223544z10-k.htm 10-K QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 10-K (Mark one) ý ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 2014 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHAN

February 18, 2015 EX-99.1

DATALINK REPORTS 2014 FOURTH QUARTER AND YEAR-END OPERATING RESULTS 12-Month Revenues Up 6.1%, Including 16% Increase in Professional Services Revenues; Record Results in Line with Guidance

Exhibit 99.1 DATALINK REPORTS 2014 FOURTH QUARTER AND YEAR-END OPERATING RESULTS 12-Month Revenues Up 6.1%, Including 16% Increase in Professional Services Revenues; Record Results in Line with Guidance EDEN PRAIRIE, Minn., February 18, 2015 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its fourth quarter and the year ended Dec

February 18, 2015 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 February 18, 2015 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

February 17, 2015 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 11, 2015 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

February 12, 2015 SC 13G/A

DTLK / Datalink Corp. / Wellington Management Group LLP - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 3 )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2014 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this S

February 12, 2015 SC 13G

DTLK / Datalink Corp. / Wellington Trust Co NA - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2014 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sch

February 10, 2015 SC 13G/A

DTLK / Datalink Corp. / Wellington Management Group LLP - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 4 )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) January 30, 2015 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sc

January 14, 2015 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

8-K 1 a15-232318k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 13, 2015 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorpo

January 14, 2015 EX-10.1

FIRST AMENDMENT TO CREDIT AGREEMENT

EXHIBIT 10.1 FIRST AMENDMENT TO CREDIT AGREEMENT This FIRST AMENDMENT TO CREDIT AGREEMENT (“Amendment”), is made effective as of January 9, 2015 (the “First Amendment Date”), by and between DATALINK CORPORATION, a Minnesota corporation, having its chief executive office located at 10050 Crosstown Circle, Suite 500, Eden Prairie, Minnesota 55344 (“Borrower), and CASTLE PINES CAPITAL LLC, a Delaware

December 22, 2014 CORRESP

DTLK / Datalink Corp. CORRESP - -

CORRESP 1 filename1.htm December 22, 2014 VIA EDGAR SYSTEM U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street N.E. Washington, D.C. 20549 Attention: Mr. Stephen Krikorian, Accounting Branch Chief Mr. Ryan Rohn, Staff Accountant Re: Datalink Corporation Form 10-K for the Fiscal Year ended December 31, 2013 Filed March 17, 2014 File No. 000-29758 Dear Messrs. Krikor

November 14, 2014 CORRESP

DTLK / Datalink Corp. CORRESP - -

November 14, 2014 VIA EDGAR SYSTEM U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street N.E. Washington, D.C. 20549 Attention: Mr. Stephen Krikorian, Accounting Branch Chief Mr. Ryan Rohn, Staff Accountant Re: Datalink Corporation Form 10-K for the Fiscal Year ended December 31, 2013 Filed March 17, 2014 File No. 000-29758 Dear Messrs. Krikorian and Rohn: On behalf

November 10, 2014 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: September 30, 2014 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission file numb

October 21, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 October 21, 2014 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

October 21, 2014 EX-99.1

DATALINK REPORTS 2014 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Third Quarter and nine Month Revenues Up 4% and 5% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2014 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Third Quarter and nine Month Revenues Up 4% and 5% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., October 21, 2014 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its third quarter and nine months that ended September 30, 2014. Revenues for the q

October 20, 2014 EX-10.1

DATALINK CORPORATION Restricted Stock Award Agreement

Exhibit 10.1 DATALINK CORPORATION Restricted Stock Award Agreement Datalink Corporation, a Minnesota corporation (the “Company”) hereby grants to you, the Grantee named below, the number of shares of the Company’s common stock set forth in the table below (the “Restricted Shares”). This Award of Restricted Shares (“Restricted Stock Award”) shall be subject to the terms and conditions set forth in

October 20, 2014 8-K

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Financial Statements and Exhibits, Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 18, 2014 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

October 20, 2014 EX-4.1

COMMON STOCK PURCHASE AGREEMENT

Exhibit 4.1 COMMON STOCK PURCHASE AGREEMENT THIS COMMON STOCK PURCHASE AGREEMENT (this “Agreement”) is made and entered into as of October 18, 2014 by and between Datalink Corporation, a Minnesota corporation (“Parent”), Mars Acquisition, Inc., a California corporation (“Merger Sub”), and each other signatory hereto (each, an “Transferring Seller” and, collectively, the “Transferring Sellers”). Ce

October 20, 2014 EX-99.1

10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK ACQUIRES IT SOLUTIONS PROVIDER BEAR DATA SOLUTIONS, INC. Acquisition Will Expand Key West Coast Market; Company Also Updates Q3 Guidance

Exhibit 99.1 10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK ACQUIRES IT SOLUTIONS PROVIDER BEAR DATA SOLUTIONS, INC. Acquisition Will Expand Key West Coast Market; Company Also Updates Q3 Guidance EDEN PRAIRIE, Minn., October 20, 2014 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today announced an agreement to acquire privately held

October 20, 2014 EX-2.1

AGREEMENT AND PLAN OF MERGER by and among BEAR DATA SOLUTIONS, INC. DATALINK CORPORATION, MARS ACQUISITION, INC., Fortis Advisors LLC, as Representative of the Securityholders October 18, 2014

EX-2.1 2 a14-226471ex2d1.htm EX-2.1 Exhibit 2.1 AGREEMENT AND PLAN OF MERGER by and among BEAR DATA SOLUTIONS, INC. DATALINK CORPORATION, MARS ACQUISITION, INC., and Fortis Advisors LLC, as Representative of the Securityholders October 18, 2014 TABLE OF CONTENTS Page ARTICLE I MERGER 2 1.01 The Merger 2 1.02 Conversion of Company Shares 2 1.03 Determination of Merger Consideration 2 1.04 Exchange

August 8, 2014 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

10-Q 1 a14-13003110q.htm 10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: June 30, 2014 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period fro

July 24, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 July 24, 2014 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

July 24, 2014 EX-99.1

DATALINK REPORTS 2014 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 8% and 6% Year-Over-Year, Respectively Revenue and Earnings Exceed High-End of Guidance

Exhibit 99.1 DATALINK REPORTS 2014 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 8% and 6% Year-Over-Year, Respectively Revenue and Earnings Exceed High-End of Guidance EDEN PRAIRIE, Minn., July 24, 2014 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its second quarter and six months tha

July 22, 2014 EX-99

10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK CORPORATION ADDS NEW BOARD MEMBER Technology Industry Veteran Mercedes A. Walton to Join Board

Exhibit 99 10050 Crosstown Circle, Suite 500, Eden Prairie, MN 55344 DATALINK CORPORATION ADDS NEW BOARD MEMBER Technology Industry Veteran Mercedes A.

July 22, 2014 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 22, 2014 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

June 10, 2014 SC 13G/A

DTLK / Datalink Corp. / Wellington Management Group LLP - DISCLOSURE DOCUMENT Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) May 30, 2014 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedul

May 22, 2014 8-K

Submission of Matters to a Vote of Security Holders - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 22, 2014 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

May 9, 2014 EX-10.1

Datalink Corporation 2011 Incentive Compensation Plan Deferred Stock Unit Master Agreement (2014 Awards)

Exhibit 10.1 Datalink Corporation 2011 Incentive Compensation Plan Deferred Stock Unit Master Agreement (2014 Awards) This is a Deferred Stock Unit Master Agreement (the “Agreement”), effective as of , 2014, between Datalink Corporation, a Minnesota corporation (the “Company”), and you, . Any capitalized term used but not defined in this Agreement shall have the meaning set forth in the Plan as it

May 9, 2014 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

10-Q 1 a14-9612110q.htm 10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: March 31, 2014 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period fro

May 6, 2014 EX-99.1

DATALINK REPORTS 2014 FIRST QUARTER OPERATING RESULTS First-Quarter Revenues Up 5% Year-Over-Year, Including 15% Increase in Services

Exhibit 99.1 DATALINK REPORTS 2014 FIRST QUARTER OPERATING RESULTS First-Quarter Revenues Up 5% Year-Over-Year, Including 15% Increase in Services EDEN PRAIRIE, Minn., May 6, 2014 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its first quarter ended March 31, 2014. Revenues for the quarter ended March 31, 2014, increased 5% to

May 6, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K 1 a14-1209618k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 May 6, 2014 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization)

April 8, 2014 EX-99.1

2013

Exhibit 99.1 Letter to Our Shareholders Dear Shareholders, Four years ago, Datalink embarked on a growth strategy that involved diversifying our legacy storage business with new products and services to increase our footprint in the data center. That included embracing converged data center infrastructures, virtualization, cloud computing, and other new technologies that were beginning to transfor

April 8, 2014 DEF 14A

- DEF 14A

DEF 14A 1 a2219354zdef14a.htm DEF 14A QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant ý Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary P

April 8, 2014 8-K

Regulation FD Disclosure, Financial Statements and Exhibits - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 April 8, 2014 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

March 17, 2014 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 10-K

10-K 1 a2218827z10-k.htm 10-K QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 10-K (Mark one) ý ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 2013 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHAN

February 20, 2014 EX-99.1

DATALINK REPORTS 2013 FOURTH QUARTER AND YEAR-END OPERATING RESULTS Fourth Quarter and Annual Revenues Up 18% and 21% Year-Over-Year, Respectively; Record Results in Line with Updated Guidance

Exhibit 99.1 DATALINK REPORTS 2013 FOURTH QUARTER AND YEAR-END OPERATING RESULTS Fourth Quarter and Annual Revenues Up 18% and 21% Year-Over-Year, Respectively; Record Results in Line with Updated Guidance EDEN PRAIRIE, Minn., February 20, 2014 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its fourth quarter and the year ended

February 20, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 February 20, 2014 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

February 14, 2014 SC 13G/A

DTLK / Datalink Corp. / Wellington Management Group LLP - DISCLOSURE DOCUMENT Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2013 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sc

February 14, 2014 SC 13G/A

DTLK / Datalink Corp. / Wellington Trust Co NA - DISCLOSURE DOCUMENT Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2013 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sc

January 14, 2014 EX-99.1

DATALINK UPDATES 2013 FOURTH QUARTER REVENUE AND EPS GUIDANCE Announces Upcoming Investor Conferences

EXHIBIT 99.1 DATALINK UPDATES 2013 FOURTH QUARTER REVENUE AND EPS GUIDANCE Announces Upcoming Investor Conferences Eden Prairie, Minn., January 14, 2014 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today announced that it expects to exceed its previous revenue and earnings guidance for the fourth quarter of 2013. The company now expects fourth quarter 2

January 14, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K 1 a14-345818k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 January 14, 2014 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organizati

December 26, 2013 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 23, 2013 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

November 26, 2013 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 26, 2013 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

November 8, 2013 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

10-Q 1 a13-19566110q.htm 10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: September 30, 2013 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition perio

October 22, 2013 EX-99.1

DATALINK REPORTS 2013 THIRD QUARTER AND NINE MONTH OPERATING Third Quarter and Nine Month Revenues Up 33% and 23% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2013 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Third Quarter and Nine Month Revenues Up 33% and 23% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., October 22, 2013 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its third quarter and nine months that ended September 30, 2013. Revenues for the

October 22, 2013 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 October 22, 2013 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

August 14, 2013 8-K

Other Events - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 August 14, 2013 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

August 9, 2013 EX-99.1

Datalink Announces Pricing of Common Stock Offering

Exhibit 99.1 Datalink Announces Pricing of Common Stock Offering EDEN PRAIRIE, Minn.—(BUSINESS WIRE)—Aug. 9, 2013— Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, announced today the pricing of an underwritten public offering of 3,300,000 shares of its common stock at $11.00 per share. The underwriters have a 30-day option to purchase, at the same price per

August 9, 2013 EX-1.1

DATALINK CORPORATION 3,795,000 Shares* Common Stock ($0.001 par value per share) Underwriting Agreement

Exhibit 1.1 Execution Version DATALINK CORPORATION 3,795,000 Shares* Common Stock ($0.001 par value per share) Underwriting Agreement August 8, 2013 CANACCORD GENUITY INC. 99 High Street, Suite 1200 Boston, MA 02110 As representative of the several Underwriters named in Schedule I hereto Dear Sirs: Datalink Corporation, a Minnesota corporation (the “Company”), proposes, subject to the terms and co

August 9, 2013 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 August 8, 2013 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

August 9, 2013 424B2

3,300,000 Shares Datalink Corporation Common Stock

Use these links to rapidly review the document TABLE OF CONTENTS TABLE OF CONTENTS Filed Pursuant to Rule 424(b)(2) Registration Statement No.

August 5, 2013 424B5

Subject to completion, dated August 5, 2013

424B5 1 a2216179z424b5.htm 424B5 Use these links to rapidly review the document TABLE OF CONTENTS TABLE OF CONTENTS The information in this prospectus supplement and the accompanying prospectus is not complete and may be changed. This prospectus supplement and the accompanying prospectus are not an offer to sell these securities and we are not soliciting an offer to buy these securities in any sta

August 2, 2013 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

10-Q 1 a13-13661110q.htm 10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: June 30, 2013 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period fro

July 25, 2013 EX-99.1

DATALINK REPORTS 2013 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 23% and 18% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2013 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 23% and 18% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., July 25, 2013 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its second quarter and six months that ended June 30, 2013. Revenues for the quarter

July 25, 2013 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 July 25, 2013 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

July 18, 2013 8-K

Entry into a Material Definitive Agreement, Termination of a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 17, 2013 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

July 18, 2013 EX-10.1

CREDIT AGREEMENT

Exhibit 10.1 CREDIT AGREEMENT THIS CREDIT AGREEMENT (this “Agreement”) is entered into as of July 17, 2013 (the “Effective Date”), by and between DATALINK CORPORATION, a Minnesota corporation (“Borrower”) and CASTLE PINES CAPITAL LLC, a Delaware limited liability company (“CPC”). Unless otherwise defined within this Credit Agreement, capitalized terms have the meaning set forth in Exhibit A, attac

June 25, 2013 CORRESP

-

CORRESP 1 filename1.htm Datalink Corporation 10050 Crosstown Circle, Suite 500 Eden Prairie, MN 55344 June 25, 2013 VIA EDGAR Securities and Exchange Commission Division of Corporation Finance 100 F. Street, N.E. Washington, D.C. 20549 Re: Datalink Corporation Registration Statement on Form S-3 File No. 333-188212 Ladies and Gentlemen: Pursuant to Rule 461 under the Securities Act of 1933, as amen

June 13, 2013 EX-4.5

DATALINK CORPORATION [ ], TRUSTEE SUBORDINATED DEBT SECURITIES DATED AS OF

Exhibit 4.5 DATALINK CORPORATION TO [ ], TRUSTEE SUBORDINATED DEBT SECURITIES INDENTURE DATED AS OF TABLE OF CONTENTS ARTICLE ONE DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION SECTION 101. Definitions 1 SECTION 102. Compliance Certificates and Opinions 7 SECTION 103. Form of Documents Delivered to Trustee 8 SECTION 104. Acts of Holders 9 SECTION 105. Notices, Etc. to Trustee and Company

June 13, 2013 EX-12.1

Datalink Corporation Ratio of Earnings to Fixed Charges (in thousands)

Exhibit 12.1 Datalink Corporation Ratio of Earnings to Fixed Charges (in thousands) Three Months Ended March 31, Year Ended December 31, 2013 2012 2011 2010 2009 2008 Ratio of Earnings to Fixed Charges: Earnings (loss) before income taxes $ 1,882 $ 17,721 $ 16,803 $ 3,992 $ (358 ) $ 5,632 Fixed charges from operations Interest expense and amortization of debt discount and issuance costs on all ind

June 13, 2013 S-3/A

- S-3/A

Use these links to rapidly review the document TABLE OF CONTENTS Table of Contents As filed with the Securities and Exchange Commission on June 13, 2013 Registration No.

June 13, 2013 CORRESP

-

Jonathan Zimmerman Partner [email protected] 612-766-8419 Faegre Baker Daniels LLP 2200 Wells Fargo Center 90 South Seventh Street Minneapolis Minnesota 55402-3901 Phone +1 612 766 7000 Fax +1 612 766 1600 June 13, 2013 Via Overnight Delivery and by EDGAR Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Attn: Matthew Crispino, At

June 13, 2013 EX-4.4

DATALINK CORPORATION [ ], TRUSTEE DEBT SECURITIES DATED AS OF [ ]

Exhibit 4.4 DATALINK CORPORATION TO [ ], TRUSTEE DEBT SECURITIES INDENTURE DATED AS OF [ ] TABLE OF CONTENTS ARTICLE ONE DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION SECTION 101. Definitions 1 SECTION 102. Compliance Certificates and Opinions 7 SECTION 103. Form of Documents Delivered to Trustee 7 SECTION 104. Acts of Holders 8 SECTION 105. Notices, Etc. to Trustee and Company 10 SECTIO

June 11, 2013 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 6, 2013 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

May 23, 2013 8-K

Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 22, 2013 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

May 10, 2013 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

10-Q 1 a13-8306110q.htm 10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: March 31, 2013 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period fro

April 29, 2013 S-3

- S-3

Table of Contents As filed with the Securities and Exchange Commission on April 29, 2013 Registration No.

April 29, 2013 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 April 29, 2013 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

April 29, 2013 EX-99.1

DATALINK REPORTS 2013 FIRST QUARTER OPERATING RESULTS Record First Quarter Revenues, Marking 12% Year-over-Year Increase

Exhibit 99.1 EXHIBITS INDEX Exhibit 99.1 Press release dated April 29, 2013 announcing the Company’s first quarter ending March 31, 2013 earnings (furnished pursuant to Item 12). DATALINK REPORTS 2013 FIRST QUARTER OPERATING RESULTS Record First Quarter Revenues, Marking 12% Year-over-Year Increase EDEN PRAIRIE, Minn., April 29, 2013 — Datalink (Nasdaq: DTLK), a leading provider of data center inf

April 29, 2013 EX-12.1

Datalink Corporation Ratio of Earnings to Fixed Charges (in thousands)

Exhibit 12.1 Datalink Corporation Ratio of Earnings to Fixed Charges (in thousands) Year Ended December 31, 2012 2011 2010 2009 2008 Ratio of Earnings to Fixed Charges: Earnings (loss) before income taxes $ 17,721 $ 16,803 $ 3,992 $ (358 ) $ 5,632 Fixed charges from operations Interest expense and amortization of debt discount and issuance costs on all indebtedness 56 40 — — — Interest included in

April 10, 2013 EX-99.1

2012

Exhibit 99.1 Letter to Our Shareholders Dear Shareholders, Over the past several years, Datalink has executed against a growth plan to capitalize on the transformational cloud movement. We helped customers evolve to a next-generation data center by unifying their infrastructures and maximizing the business benefits of cloud. In 2012, that plan helped us deliver a strong financial performance for t

April 10, 2013 DEF 14A

- DEF 14A

QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

April 10, 2013 8-K

Regulation FD Disclosure, Financial Statements and Exhibits - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 April 10, 2013 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

April 10, 2013 EX-99.2

Twelve Months Ended

Exhibit 99.2 Non-GAAP Details Non-GAAP operating income excludes the impact from acquisition accounting adjustments to deferred revenue and costs, stock-based compensation expense, and amortization of acquisition intangible assets, integration and transaction costs related to acquisitions. Non-GAAP operating income is not in accordance with, or an alternative for measures prepared in accordance wi

March 21, 2013 EX-99.2

AMENDED AND RESTATED REVOLVING LINE OF CREDIT NOTE

Exhibit 99.2 AMENDED AND RESTATED REVOLVING LINE OF CREDIT NOTE $20,000,000.00 Minneapolis, Minnesota March 19, 2013 FOR VALUE RECEIVED, the undersigned DATALINK CORPORATION (“Borrower”) promises to pay to the order of WELLS FARGO BANK, NATIONAL ASSOCIATION (“Bank”) at its Regional Commercial Banking Office located in Minneapolis, Minnesota, or at such other place as the holder hereof may designat

March 21, 2013 EX-99.3

FIFTH AMENDMENT TO CREDIT AGREEMENT

Exhibit 99.3 FIFTH AMENDMENT TO CREDIT AGREEMENT THIS FIFTH AMENDMENT TO CREDIT AGREEMENT (“Amendment”) dated as of March 19, 2013, is made by and between DATALINK CORPORATION, a Minnesota corporation (the “Borrower”), and WELLS FARGO BANK, NATIONAL ASSOCIATION, a national banking association (“Bank”). A. Borrower and Bank are parties to that certain Credit Agreement dated as of March 31, 2011 (as

March 21, 2013 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 March 19, 2013 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

March 15, 2013 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 10-K

10-K 1 a2213605z10-k.htm 10-K QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 10-K (Mark one) ý ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 2012 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHAN

February 19, 2013 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 13, 2013 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

February 14, 2013 SC 13G

DTLK / Datalink Corp. / Wellington Trust Co NA - DISCLOSURE DOCUMENT Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2012 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sch

February 14, 2013 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 February 14, 2013 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

February 14, 2013 EX-99.1

DATALINK REPORTS 2012 FOURTH QUARTER AND YEAR-END OPERATING RESULTS Record Fourth Quarter and Annual Revenue Up 28% and 29% Year-Over-Year, Respectively

Exhibit 99.1 EXHIBITS INDEX Exhibit 99.1 Press release dated February 14, 2013 announcing the Company’s fourth quarter and year ending December 31, 2012 earnings (furnished pursuant to Item 12). DATALINK REPORTS 2012 FOURTH QUARTER AND YEAR-END OPERATING RESULTS Record Fourth Quarter and Annual Revenue Up 28% and 29% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., February 14, 2013 — Datalink (N

February 14, 2013 SC 13G

DTLK / Datalink Corp. / WELLINGTON MANAGEMENT GROUP LLP - DISCLOSURE DOCUMENT Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2012 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sch

December 21, 2012 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

8-K 1 a12-2996518k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 4, 2012 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorp

November 9, 2012 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

10-Q 1 a12-18759110q.htm 10-Q Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: September 30, 2012 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition perio

October 25, 2012 EX-99.1

DATALINK REPORTS 2012 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Third Quarter and Nine Month Revenues Up 16% and 30% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2012 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Third Quarter and Nine Month Revenues Up 16% and 30% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., October 25, 2012 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its third quarter and nine months that ended September 30, 2012. Revenues for the

October 25, 2012 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 October 25, 2012 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

October 4, 2012 EX-99.1

Datalink Announces Intent to Purchase Strategic Technologies Acquisition Will Expand Market Share in North Carolina, Florida and the Mid-Atlantic

Exhibit 99.1 FOR IMMEDIATE RELEASE Datalink Announces Intent to Purchase Strategic Technologies Acquisition Will Expand Market Share in North Carolina, Florida and the Mid-Atlantic EDEN PRAIRIE, Minn., October 2, 2012 — Datalink (NASDAQ: DTLK), a leading provider of data center infrastructure and services, today announced a definitive agreement to acquire substantially all of the assets, and liabi

October 4, 2012 8-K

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant, Results of Operations and Financial Condition, Completion of Acquisition or Disposition of Assets - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 2, 2012 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

October 4, 2012 EX-2.1

ASSET PURCHASE AGREEMENT BY AND AMONG DATALINK CORPORATION, STI ACQUISITION CORP., STRATEGIC TECHNOLOGIES, INC., MIDAS MEDICI GROUP HOLDINGS, INC. October 2, 2012

Exhibit 2.1 ASSET PURCHASE AGREEMENT BY AND AMONG DATALINK CORPORATION, STI ACQUISITION CORP., STRATEGIC TECHNOLOGIES, INC., AND MIDAS MEDICI GROUP HOLDINGS, INC. October 2, 2012 TABLE OF CONTENTS ARTICLE 1 PURCHASE OF ACQUIRED ASSETS AND RELATED TERMS 1 1.1 Certain Definitions Relating to Acquired Assets 1 1.2 Sale and Purchase of Acquired Assets 4 1.3 Excluded Assets 5 1.4 Assumed Liabilities 5

October 4, 2012 EX-99.2

Datalink Announces Closing of the Purchase of Strategic Technologies and Provides Third Quarter Guidance Update Acquisition Will Expand Market Share in North Carolina, Florida and the Mid-Atlantic

Exhibit 99.2 FOR IMMEDIATE RELEASE Datalink Announces Closing of the Purchase of Strategic Technologies and Provides Third Quarter Guidance Update Acquisition Will Expand Market Share in North Carolina, Florida and the Mid-Atlantic EDEN PRAIRIE, Minn., October 4, 2012 — Datalink (NASDAQ: DTLK), a leading provider of data center infrastructure and services, today announced the closing of the transa

October 4, 2012 EX-99.5

FOURTH AMENDMENT TO CREDIT AGREEMENT

Exhibit 99.5 FOURTH AMENDMENT TO CREDIT AGREEMENT THIS FOURTH AMENDMENT TO CREDIT AGREEMENT (“Amendment”) dated as of October 2, 2012, is made by and between DATALINK CORPORATION, a Minnesota corporation (the “Borrower”), and WELLS FARGO BANK, NATIONAL ASSOCIATION, a national banking association (“Bank”). A. Borrower and Bank are parties to that certain Credit Agreement dated as of March 31, 2011

October 4, 2012 EX-99.4

AMENDED AND RESTATED REVOLVING LINE OF CREDIT NOTE

Exhibit 99.4 AMENDED AND RESTATED REVOLVING LINE OF CREDIT NOTE $15,000,000.00 Minneapolis, Minnesota October 2, 2012 FOR VALUE RECEIVED, the undersigned DATALINK CORPORATION (“Borrower”) promises to pay to the order of WELLS FARGO BANK, NATIONAL ASSOCIATION (“Bank”) at its Regional Commercial Banking Office located in Minneapolis, Minnesota, or at such other place as the holder hereof may designa

August 10, 2012 10-Q

FORM 10-Q UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

10-Q 1 a12-13796110q.htm 10-Q Table of Contents FORM 10-Q UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: June 30, 2012 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period fro

August 3, 2012 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 August 3, 2012 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

August 3, 2012 EX-10.2

WELLS FARGO AMENDED AND RESTATED REVOLVING LINE OF CREDIT NOTE

EX-10.2 2 a12-175331ex10d2.htm EX-10.2 Exhibit 10.2 WELLS FARGO AMENDED AND RESTATED REVOLVING LINE OF CREDIT NOTE $10,000,000.00 Minneapolis, Minnesota July 31, 2012 FOR VALUE RECEIVED, the undersigned DATALINK CORPORATION (“Borrower”) promises to pay to the order of WELLS FARGO BANK, NATIONAL ASSOCIATION (“Bank”) at its Regional Commercial Banking Office located in Minneapolis, Minnesota, or at

August 3, 2012 EX-10.3

WELLS FARGO THIRD AMENDMENT TO CREDIT AGREEMENT

Exhibit 10.3 WELLS FARGO THIRD AMENDMENT TO CREDIT AGREEMENT THIS THIRD AMENDMENT TO CREDIT AGREEMENT (“Amendment”) dated as of July 31, 2012, is made by and between DATALINK CORPORATION, a Minnesota corporation (the “Borrower”), and WELLS FARGO BANK, NATIONAL ASSOCIATION, a national banking association (“Bank”). A. Borrower and Bank are parties to that certain Credit Agreement dated as of March 3

July 26, 2012 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 July 26, 2012 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

July 26, 2012 EX-99.2

Second Quarter 2012 Investor Call July 26, 2012 Paul Lidsky, CEO Greg Barnum, CFO

Exhibit 99.2 Q2 2012 Investor Conference Call Script July 26, 2012 Paul Lidsky: Thank you, operator. Good afternoon. I’d like to welcome everyone to this afternoon’s conference call. Thank you for joining us. With me today is Greg Barnum, our Vice President of Finance and Chief Financial Officer. I’ll now turn the call over to Greg to discuss our second-quarter results and then I will provide some

July 26, 2012 EX-99.1

DATALINK REPORTS 2012 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 34% and 36% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2012 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Second Quarter and Six Month Revenues Up 34% and 36% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., July 26, 2012 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its second quarter and six months that ended June 30, 2012. Revenues for the quarter

July 13, 2012 S-8

- S-8

S-8 1 a12-161391s8.htm S-8 As filed with the Securities and Exchange Commission on July 13, 2012. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 DATALINK CORPORATION (Exact Name of Registrant as Specified in Its Charter) Minnesota (State or Other Jurisdiction of Incorporation or Organiz

May 15, 2012 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 10, 2012 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of (Commission File No.

May 10, 2012 EX-10.1

KAREN CLARY EMPLOYMENT AGREEMENT EMPLOYMENT AGREEMENT

EX-10.1 2 a12-85851ex10d1.htm EX-10.1 Exhibit 10.1 KAREN CLARY EMPLOYMENT AGREEMENT EMPLOYMENT AGREEMENT THIS EMPLOYMENT AGREEMENT (the “Agreement”) is made and entered into by and between Datalink Corporation, a Minnesota corporation (the “Company”), and Karen Clary (the “Executive”) effective as of the 16th day of January, 2012. R E C I T A L S: WHEREAS, the Company is a provider of data center

May 10, 2012 10-Q

FORM 10-Q UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

10-Q 1 a12-8585110q.htm 10-Q Table of Contents FORM 10-Q UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: March 31, 2012 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period fro

April 25, 2012 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 April 25, 2012 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

April 25, 2012 EX-99.1

DATALINK REPORTS 2012 FIRST QUARTER OPERATING RESULTS Record First Quarter Revenues and Net Earnings, Up 39% and 24% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2012 FIRST QUARTER OPERATING RESULTS Record First Quarter Revenues and Net Earnings, Up 39% and 24% Year-Over-Year, Respectively EDEN PRAIRIE, Minn., April 25, 2012 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its first quarter that ended March 31, 2012. Revenues for the quarter increased 39% to a

April 25, 2012 EX-99.2

First Quarter 2012 Investor Call April 25, 2012 Paul Lidsky, CEO Greg Barnum, CFO

Exhibit 99.2 Q1 2012 Investor Conference Call Script April 25, 2012 Paul Lidsky: Thank you, operator. Good afternoon. I’d like to welcome everyone to this afternoon’s conference call. Thank you for joining us. With me today is Greg Barnum, our Vice President of Finance and Chief Financial Officer. I’ll now turn the call over to Greg to discuss our first-quarter results and our outlook for the seco

March 30, 2012 DEF 14A

- DEF 14A

QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

March 15, 2012 EX-10.18

LEASE AGREEMENT [Crosstown Centre, Eden Prairie, MN]

EX-10.18 2 a2208070zex-1018.htm EX-10.18 Exhibit 10.18 LEASE AGREEMENT [Crosstown Centre, Eden Prairie, MN] This Lease is made and entered into as of the Effective Date, by and between IRET PROPERTIES, A NORTH DAKOTA LIMITED PARTNERSHIP, as Landlord, and MIDWAVE CORPORATION, a Delaware corporation, as Tenant. Landlord and Tenant acknowledge that Landlord currently leases the Premises to BEST BUY S

March 15, 2012 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 10-K

10-K 1 a2208070z10-k.htm 10-K QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 10-K (Mark one) ý ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 2011 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHAN

March 15, 2012 EX-10.19

FIRST AMENDMENT TO LEASE

EXHIBIT 10.19 FIRST AMENDMENT TO LEASE THIS AMENDMENT (the “Amendment”) is entered into between IRET PROPERTIES, A NORTH DAKOTA LIMITED PARTNERSHIP (“Landlord”), and MV SUB, INC., a Minnesota corporation (“Tenant”). This Amendment shall be effective as of the date set forth below in Landlord’s signature block. A. Landlord and Tenant (as successor in interest to Midwave Corporation) are parties to

February 16, 2012 8-K/A

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K/A 1 a12-518328ka.htm 8-K/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K/A CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 February 16, 2012 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or or

February 16, 2012 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 February 16, 2012 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

February 16, 2012 EX-99.2

Q4 &Year End 2011 Investor Conference Call Script

Exhibit 99.2 Q4 &Year End 2011 Investor Conference Call Script February 16, 2012 Paul Lidsky: Thank you, operator. Good morning. I’d like to welcome everyone to this morning’s conference call. Thank you for joining us. With me today is Greg Barnum, our Vice President of Finance and Chief Financial Officer. I’ll now turn the call over to Greg to discuss our fourth-quarter results and our outlook fo

February 16, 2012 EX-99.1

DATALINK REPORTS 2011 FOURTH QUARTER AND YEAR-END OPERATING RESULTS Record Fourth Quarter and Annual Revenue Up 26% and 29% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2011 FOURTH QUARTER AND YEAR-END OPERATING RESULTS Record Fourth Quarter and Annual Revenue Up 26% and 29% Year-Over-Year, Respectively CHANHASSEN, Minn., February 16, 2012 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its fourth quarter and year that ended December 31, 2011. Revenues for the quart

February 16, 2012 EX-99.1

DATALINK CLARIFIES GUIDANCE FOR FIRST QUARTER 2012

Exhibit 99.1 DATALINK CLARIFIES GUIDANCE FOR FIRST QUARTER 2012 CHANHASSEN, Minn., February 16, 2012 — Datalink is clarifying information included in its release dated February 16, 2012. The beginning of the first paragraph under “Outlook” read as follows: “With the strong start to the new year, Datalink’s first quarter guidance suggests a 17% to 24% year-over-year revenue increase in fiscal 2012.

February 14, 2012 SC 13G/A

DTLK / Datalink Corp. / DIKER MANAGEMENT LLC Passive Investment

Document Converted by Corporate-Insiders.com UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 5) Datalink Corp. (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2011 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to design

February 14, 2012 SC 13G/A

DTLK / Datalink Corp. / WELLINGTON MANAGEMENT GROUP LLP - DISCLOSURE DOCUMENT Passive Investment

SC 13G/A 1 secfiling.htm DISCLOSURE DOCUMENT UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2011 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to

February 14, 2012 SC 13G/A

DTLK / Datalink Corp. / Wellington Trust Co NA - DISCLOSURE DOCUMENT Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* Datalink Corporation (Name of Issuer) Common Stock (Title of Class of Securities) 237934104 (CUSIP Number) December 31, 2011 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Sc

December 21, 2011 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Entry into a Material Definitive Agreement, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

8-K 1 a11-3212318k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 December 16, 2011 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organiza

December 16, 2011 EX-99.4

PRO FORMA FINANCIAL INFORMATION UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

Exhibit 99.4 PRO FORMA FINANCIAL INFORMATION UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS On October 3, 2011, we completed our acquisition of substantially all of the assets, and selected liabilities, of Midwave Corporation, a Minneapolis based company. Midwave Corporation is an information technology services and solutions firm focused on optimizing the data centers and information

December 16, 2011 EX-99.2

MIDWAVE CORPORATION INTERIM FINANCIAL STATEMENTS OCTOBER 1, 2011 and SEPTEMBER 25, 2010

Exhibit 99.2 MIDWAVE CORPORATION INTERIM FINANCIAL STATEMENTS OCTOBER 1, 2011 and SEPTEMBER 25, 2010 CONTENTS Page Financial Statements Balance Sheets 2 Statements of Operations 3 Statements of Cash Flows 4 Notes to the Financial Statements 5 - 9 Midwave Corporation Balance Sheets (Unaudited) October 1, 2011 September 25, 2010 Assets Current assets Cash and cash equivalents $ 2,270,780 $ 2,679,725

December 16, 2011 8-K/A

Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K/A Amendment No.

December 16, 2011 EX-99.3

MIDWAVE CORPORATION AUDITED FINANCIAL STATEMENTS DECEMBER 25, 2010 and DECEMBER 26, 2009

Exhibit 99.3 MIDWAVE CORPORATION AUDITED FINANCIAL STATEMENTS DECEMBER 25, 2010 and DECEMBER 26, 2009 CONTENTS Page Independent Auditor’s Report 2 Financial Statements Balance Sheet 3 Statements of Operations 4 Statements of Stockholders’ Equity 5 Statements of Cash Flows 6 Notes to the Financial Statements 7 - 12 INDEPENDENT AUDITOR’S REPORT Stockholders and Board of Directors Midwave Corporation

November 10, 2011 10-Q

FORM 10-Q SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

Table of Contents FORM 10-Q SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: September 30, 2011 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission file number: 00029758 D

November 10, 2011 EX-10.2

Stuart D. Missling / Director of Operations / Datalink Corporation

Exhibit 10.2 [Logo] 10/4/2011 Stuart D. Missling / Director of Operations / Datalink Corporation Re: Lease Termination Agreement Whereas, Landlord and Tenant agree and now desire to provide termination of the lease agreement between High Street & Datalink Corporation for the rental property located at 7205 Golden Triangle Dr., Eden Prairie, MN 55344, and the return of the Leased Premises to Landlo

November 10, 2011 EX-10.1

STANDARD FORM INDUSTRIAL BUILDING LEASE

Exhibit 10.1 STANDARD FORM INDUSTRIAL BUILDING LEASE 1. BASIC TERMS. This Section 1 contains the Basic Terms of this Lease between Landlord and Tenant, named below. Other Sections of the Lease referred to in this Section 1 explain and define the Basic Terms and are to be read in conjunction with the Basic Terms. 1.1. Date of Lease: June 24, 2011 1.2. Landlord: Golden Triangle Tech Center Investors

October 19, 2011 EX-99.2

Q3 2011 Investor Conference Call Script

Exhibit 99.2 Q3 2011 Investor Conference Call Script October 19, 2011 Paul Lidsky: Thank you, operator. Good afternoon. This is Paul Lidsky, President and Chief Executive Officer of Datalink. I’d like to welcome everyone to this afternoon’s conference call. Thank you for joining us. With me today is Greg Barnum, our Vice President of Finance and Chief Financial Officer. I’ll now turn the call over

October 19, 2011 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 October 19, 2011 (Date of Report – date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

October 19, 2011 EX-99.1

DATALINK REPORTS 2011 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Record Third Quarter and Nine Month Revenues Up 30% and 31% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2011 THIRD QUARTER AND NINE MONTH OPERATING RESULTS Record Third Quarter and Nine Month Revenues Up 30% and 31% Year-Over-Year, Respectively CHANHASSEN, Minn., October 19, 2011 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its third quarter and nine month period that ended September 30, 2011. Reven

October 11, 2011 8-K

Termination of a Material Definitive Agreement

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 3, 2011 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

October 3, 2011 EX-2.1

ASSET PURCHASE AGREEMENT BY AND AMONG DATALINK CORPORATION MV SUB, INC. MIDWAVE CORPORATION JAMES D. LESLIE ROBERT S. KROCAK JAMES D. LESLIE, AS SELLERS AGENT

Exhibit 2.1 ASSET PURCHASE AGREEMENT BY AND AMONG DATALINK CORPORATION MV SUB, INC. MIDWAVE CORPORATION JAMES D. LESLIE ROBERT S. KROCAK AND JAMES D. LESLIE, AS SELLERS AGENT TABLE OF CONTENTS ARTICLE 1 PURCHASE OF ACQUIRED ASSETS AND RELATED TERMS 1 1.1 Certain Definitions Relating to Transactions 1 1.2 Sale and Purchase of Acquired Assets 4 1.3 Excluded Assets 4 1.4 Assumed Liabilities 4 1.5 Exc

October 3, 2011 EX-99.1

Datalink Completes the Purchase of Minneapolis-Based Midwave Expands Market Share in Minnesota and the Surrounding Region Reconfirms Third Quarter 2011 Guidance

EXHIBIT 99.1 Datalink Completes the Purchase of Minneapolis-Based Midwave Expands Market Share in Minnesota and the Surrounding Region Reconfirms Third Quarter 2011 Guidance MINNEAPOLIS, Minn., October 3, 2011 — Datalink (NASDAQ: DTLK), a leading provider of data center infrastructure and services, today announced that it has acquired substantially all of the assets, and selected liabilities, of M

October 3, 2011 8-K

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Financial Statements and Exhibits, Results of Operations and Financial Condition, Completion of Acquisition or Disposition of Assets

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 3, 2011 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

August 11, 2011 10-Q

FORM 10-Q SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

Table of Contents FORM 10-Q SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 (Mark One) x Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended: June 30, 2011 or o Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to Commission file number: 00029758 DATALI

August 11, 2011 EX-10.5

DATALINK CORPORATION Incentive Stock Option Agreement Under the 2011 Incentive Compensation Plan

Exhibit 10.5 DATALINK CORPORATION Incentive Stock Option Agreement Under the 2011 Incentive Compensation Plan Datalink Corporation (the “Company”), pursuant to its 2011 Incentive Compensation Plan (the “Plan”), hereby grants an Option to purchase shares of the Company’s common stock to you, the Optionee named below. The terms and conditions of the Option Award are set forth in this Agreement, cons

August 11, 2011 EX-10.4

DATALINK CORPORATION Restricted Stock Award Agreement Under the 2011 Incentive Compensation Plan

Exhibit 10.4 DATALINK CORPORATION Restricted Stock Award Agreement Under the 2011 Incentive Compensation Plan Datalink Corporation (the “Company”), pursuant to its 2011 Incentive Compensation Plan (the “Plan”), hereby grants to you, the Grantee named below, the number of shares of the Company’s common stock set forth in the table below (the “Restricted Shares”). This Award of Restricted Shares (“R

August 11, 2011 EX-10.3

DATALINK CORPORATION Restricted Stock Award Agreement Under the 2011 Incentive Compensation Plan

Exhibit 10.3 DATALINK CORPORATION Restricted Stock Award Agreement Under the 2011 Incentive Compensation Plan Datalink Corporation (the “Company”), pursuant to its 2011 Incentive Compensation Plan (the “Plan”), hereby grants to you, the Grantee named below, the number of shares of the Company’s common stock set forth in the table below (the “Restricted Shares”). This Award of Restricted Shares (“R

August 11, 2011 EX-10.6

DATALINK CORPORATION Non-Qualified Stock Option Agreement Under the 2011 Incentive Compensation Plan

Exhibit 10.6 DATALINK CORPORATION Non-Qualified Stock Option Agreement Under the 2011 Incentive Compensation Plan Datalink Corporation (the “Company”), pursuant to its 2011 Incentive Compensation Plan (the “Plan”), hereby grants an Option to purchase shares of the Company’s common stock to you, the Optionee named below. The terms and conditions of the Option Award are set forth in this Agreement,

August 1, 2011 8-K

Entry into a Material Definitive Agreement, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 28, 2011 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

July 20, 2011 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 July 20, 2011 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

July 20, 2011 EX-99.1

DATALINK REPORTS 2011 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Record Second Quarter and Six Month Revenue Up 26% and 31% Year-Over-Year, Respectively

Exhibit 99.1 DATALINK REPORTS 2011 SECOND QUARTER AND SIX MONTH OPERATING RESULTS Record Second Quarter and Six Month Revenue Up 26% and 31% Year-Over-Year, Respectively CHANHASSEN, Minn., July 20, 2011 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its second quarter and six month period that ended June 30, 2011. Revenues for t

July 20, 2011 EX-99.2

Q2 2011 Investor Conference Call Script

Exhibit 99.2 Q2 2011 Investor Conference Call Script July 20, 2011 Paul Lidsky: Thank you, operator. Good afternoon. This is Paul Lidsky, President and Chief Executive Officer of Datalink. I’d like to welcome everyone to this afternoon’s conference call. Thank you for joining us. With me today is Greg Barnum, our Vice President of Finance and Chief Financial Officer. I’ll now turn the call over to

July 15, 2011 S-8

As filed with the Securities and Exchange Commission on July 15, 2011.

As filed with the Securities and Exchange Commission on July 15, 2011. Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 DATALINK CORPORATION (Exact Name of Registrant as Specified in Its Charter) Minnesota (State or Other Jurisdiction of Incorporation or Organization) 41-0856543 (I.R.S. E

May 13, 2011 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K Current Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 12, 2011 DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota 000-29758 41-0856543 (State or other jurisdiction of incorporation or organization) (Commission File No.

May 12, 2011 10-Q

FORM 10-Q UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549

Table of Contents FORM 10-Q UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

April 20, 2011 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 April 20, 2011 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

April 20, 2011 EX-99.1

DATALINK REPORTS 2011 FIRST QUARTER OPERATING RESULTS Record First Quarter Results Beat Revenues and Earnings Guidance

Exhibit 99.1 DATALINK REPORTS 2011 FIRST QUARTER OPERATING RESULTS Record First Quarter Results Beat Revenues and Earnings Guidance CHANHASSEN, Minn., April 20, 2011 — Datalink (Nasdaq: DTLK), a leading provider of data center infrastructure and services, today reported results for its first quarter that ended March 31, 2011. For the first quarter, revenues were $85.7 million compared to $62.5 mil

April 20, 2011 EX-99.2

Q1 2011 Investor Conference Call Script

Exhibit 99.2 Q1 2011 Investor Conference Call Script April 20, 2011 Paul Lidsky: Thank you, operator. Good afternoon. This is Paul Lidsky, President and Chief Executive Officer of Datalink. I’d like to welcome everyone to this afternoon’s conference call. Thank you for joining us. With me today is Greg Barnum, our Vice President of Finance and Chief Financial Officer. I’ll now turn the call over t

April 1, 2011 EX-10.1

CREDIT AGREEMENT

Exhibit 10.1 CREDIT AGREEMENT THIS CREDIT AGREEMENT (this “Agreement”) is entered into as of March 31, 2011, by and between Datalink Corporation, a Minnesota corporation (“Borrower”), and WELLS FARGO BANK, NATIONAL ASSOCIATION (“Bank”). RECITALS Borrower has requested that Bank extend or continue credit to Borrower as described below, and Bank has agreed to provide such credit to Borrower on the t

April 1, 2011 EX-99.1

Datalink Announces Closure on a $10 Million Credit Agreement

Exhibit 99.1 Datalink Announces Closure on a $10 Million Credit Agreement CHANHASSEN, MN — April 1, 2011 — Datalink Corporation (NASDAQ: DTLK), a leading provider of data center solutions and services, today announced that it has entered into a Credit Agreement with Wells Fargo Bank, National Association (the “Credit Agreement”). The Credit Agreement provides for a line of credit not to exceed $10

April 1, 2011 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 March 31, 2011 (Date of Report — date of earliest event reported) DATALINK CORPORATION (Exact name of registrant as specified in charter) Minnesota (State or other jurisdiction of incorporation or organization) 00029758 41-0856543 (Commission File No.

March 31, 2011 DEF 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

QuickLinks - Click here to rapidly navigate through this document UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

Fintel data has been cited in the following publications:
Daily Mail Fox Business Business Insider Wall Street Journal The Washington Post Bloomberg Financial Times Globe and Mail
NASDAQ.com Reuters The Guardian Associated Press FactCheck.org Snopes Politifact
Federal Register The Intercept Forbes Fortune Magazine TheStreet Time Magazine Canadian Broadcasting Corporation International Business Times
Cambridge University Press Investopedia MarketWatch NY Daily News Entrepreneur Newsweek Barron's El Economista