William P Scully - Insider Trading Tracker

Introduction

This page provides a comprehensive analysis of the known insider trading history of William P Scully. Insiders are officers, directors, or significant investors in a company. It is illegal for insiders to make trades in their companies based on specific, non-public information. This does not mean it is illegal for them to make any trades in their own companies. However, they must report all trades to the SEC via a Form 4. Despite these restrictions, academic research suggests that insiders - in general - tend to outperform the market in their own companies.

Average Trade Profitability

Companies with Reported Insider Positions

The SEC filings indicate William P Scully has reported holdings or trades in the following companies:

How to Interpret the Charts

The following charts show the stock performance of securities subsequent to each open-market, non-planned trade made by William P Scully. Non-planned trade are trades that were not made as part of a 10b5-1 trading plan. The stock performance is charted as cumulative percent change in share price. For example, if an insider trade was made on January 1, 2019, the chart will show the daily percent change of the security to the present day. If the share price were to go from $10 to $15 during this time, the cumulative percent change in share price would be 50%. A change in price from $10 to $20 would be 100%, and a change in price of $10 to $5 would be -50%.

Ultimately, we are trying to determine how closely the insider’s trades correlate to excess returns (positive or negative) in the share price in order to see if the insider is timing their trades to profit from insider information. Consider the situation where an insider was doing this. In this situation, we would expect either (a) positive returns after purchases, or (b) negative returns after sales. In the case of (a), the PURCHASE chart would show a series of upwardly sloping curves, indicating positive returns after each purchase transaction. In the case of (b), the SALE chart would show a series of downward sloping curves, indicating negative returns after each sale transaction.

However, this alone is not enough to draw conclusions. If, for example, the share price of the company was in a non-cyclical climb over many years, then we would expect all the post-purchase plots to be upwardly sloping. Likewise, non-cyclical declines over many years would result in downward sloping post-trade plots. Neither of these charts would suggest insider trading activity.

The strongest indicator would be a situation where the share price was extremely cyclical, and there were both positive signals in the PURCHASE chart and negative plots on the SALE chart. This situation would be highly suggestive of an insider that was timing trades to their financial advantage.

Insider Purchases PRTA / Prothena Corporation plc - Short Term Profit Analysis

In this section, we analyze the profitability of every unplanned, open-market insider purchase made in PRTA / Prothena Corporation plc. This analysis helps to understand if the insider consistently generates abnormal returns, and is worth following. This analysis is for one-year following each trade, and the results are theoretical.

The following table shows the most recent open market purchases that were not part of an automatic trading plan.

Trade Date	Ticker	Insider	Reported Shares	Reported Price	Adjusted Shares	Adjusted Price	Cost Basis	Days to Max	Price at Max	Max Profit ($)	Max Return (%)
2025-01-14	PRTA	SCULLY WILLIAM P	100,000	12.7904	100,000	12.7904	1,279,040	13	16.0400	324,960	25.41
2024-12-31	PRTA	SCULLY WILLIAM P	1,200	13.3652	1,200	13.3652	16,038
2024-12-31	PRTA	SCULLY WILLIAM P	800	13.3940	800	13.3940	10,715
2024-12-31	PRTA	SCULLY WILLIAM P	30,000	12.9880	30,000	12.9880	389,640
2024-12-20	PRTA	SCULLY WILLIAM P	2,000	15.9065	2,000	15.9065	31,813
2024-12-18	PRTA	SCULLY WILLIAM P	73,436	13.9260	73,436	13.9260	1,022,670

Adjusted Price is the split-adjusted price. Adjusted Shares is the split-adjusted shares.

Insider Sales PRTA / Prothena Corporation plc - Short Term Loss Analysis

In this section, we analyze the short-term loss avoidance of every unplanned, open-market insider sale made in PRTA / Prothena Corporation plc. A consistent pattern of loss avoidance may suggest that future sale transactions may predict declines in price. This analysis is for one-year following each trade, and the results are theoretical.

The following table shows the most recent open market sales that were not part of an automatic trading plan.

Trade Date	Ticker	Insider	Reported Shares	Reported Price	Adjusted Shares	Adjusted Price	Cost Basis	Days to Min	Price at Min	Max Loss Avoided ($)	Max Loss Avoided (%)
There are no known unplanned open-market trades for this insider and security combination

Adjusted Price is the split-adjusted price. Adjusted Shares is the split-adjusted shares.

Insider Purchases YTENQ / Yield10 Bioscience, Inc. - Short Term Profit Analysis

In this section, we analyze the profitability of every unplanned, open-market insider purchase made in PRTA / Prothena Corporation plc. This analysis helps to understand if the insider consistently generates abnormal returns, and is worth following. This analysis is for one-year following each trade, and the results are theoretical.

The following table shows the most recent open market purchases that were not part of an automatic trading plan.

Trade Date	Ticker	Insider	Reported Shares	Reported Price	Adjusted Shares	Adjusted Price	Cost Basis	Days to Max	Price at Max	Max Profit ($)	Max Return (%)
2015-09-17	MBLX	SCULLY WILLIAM P	31,833	2.1051	31,833	2.1051	67,012	731
2015-09-15	MBLX	SCULLY WILLIAM P	47,500	2.1529	47,500	2.1529	102,263
2015-09-15	MBLX	SCULLY WILLIAM P	47,150	2.1529	47,150	2.1529	101,509
2015-09-14	MBLX	SCULLY WILLIAM P	20,000	2.1782	20,000	2.1782	43,564
2015-09-10	MBLX	SCULLY WILLIAM P	25,000	2.7059	25,000	2.7059	67,648
2015-09-10	MBLX	SCULLY WILLIAM P	25,000	2.2059	25,000	2.2059	55,148
2015-09-08	MBLX	SCULLY WILLIAM P	40,000	2.2267	40,000	2.2267	89,068
2015-09-04	MBLX	SCULLY WILLIAM P	7,750	2.0521	7,750	2.0521	15,904
2015-09-03	MBLX	SCULLY WILLIAM P	35,000	2.1685	35,000	2.1685	75,898
2015-08-28	MBLX	SCULLY WILLIAM P	26,600	1.9944	26,600	1.9944	53,051

Adjusted Price is the split-adjusted price. Adjusted Shares is the split-adjusted shares.

Insider Sales YTENQ / Yield10 Bioscience, Inc. - Short Term Loss Analysis

In this section, we analyze the short-term loss avoidance of every unplanned, open-market insider sale made in PRTA / Prothena Corporation plc. A consistent pattern of loss avoidance may suggest that future sale transactions may predict declines in price. This analysis is for one-year following each trade, and the results are theoretical.

The following table shows the most recent open market sales that were not part of an automatic trading plan.

Trade Date	Ticker	Insider	Reported Shares	Reported Price	Adjusted Shares	Adjusted Price	Cost Basis	Days to Min	Price at Min	Max Loss Avoided ($)	Max Loss Avoided (%)
2016-09-13	MBLX	SCULLY WILLIAM P	23,333	0.3314	23,333	0.3314	7,733	730
2016-09-12	MBLX	SCULLY WILLIAM P	45,000	0.3287	45,000	0.3287	14,792
2016-09-09	MBLX	SCULLY WILLIAM P	65,000	0.3367	65,000	0.3367	21,886
2016-09-08	MBLX	SCULLY WILLIAM P	100,000	0.3555	100,000	0.3555	35,550

Adjusted Price is the split-adjusted price. Adjusted Shares is the split-adjusted shares.

Insider Trading History

This table shows the complete list of insider trades made by William P Scully as disclosed to the Securities Exchange Commission (SEC).