undamentalytics Newsletter

Walker Clifford: insider trades

Officer at Power Integrations Inc. No open-market purchases and 85 sales not made under a pre-set plan, reported from August 17, 2010 to April 4, 2025.

What happened after Walker Clifford’s sales?

After their sales, the shares moved −3.8% against the index over 12 months on average (a negative figure means selling was the right call); 64% trailed it.

With 296 insiders tested, some will look skilled or unskilled by chance alone: when we replaced each insider’s stocks with random companies bought on the same days, about 5.7 cleared the bar ahead and 23.3 behind. One record on its own proves little.

Trade by trade

Walker Clifford: trades against the S&P 500 afterwards
MeasuredTrades countedAverage vs S&P 500MedianWent the right wayYearst-statisticp-valueEvidence
Purchases, 3 months after the report 0 — — — — — — Not enough years
Purchases, 6 months after the report 0 — — — — — — Not enough years
Purchases, 12 months after the report 0 — — — — — — Not enough years
Purchases, 12 months after the trade 0 — — — — — — Not enough years
Sales, 3 months after the report 85 −2.2% −3.2% 64% 16 −1.49 0.16 No reliable evidence
Sales, 12 months after the report 85 −3.8% −8.2% 64% 16 −1.07 0.30 No reliable evidence
Sales, 12 months after the trade 85 −3.5% −10.3% 65% 16 −1.02 0.32 No reliable evidence

“Average vs S&P 500” is the stock’s return including dividends minus the index’s over the same dates, from the close on the first trading day after the report, or from the close on the trade date. Only windows that have finished are counted. For sales, a negative figure means the stock lagged after it was sold, so selling was the right call (green). “Went the right way” is the share of purchases that beat the index, or of sales that trailed it. The t-statistic uses one average per year of reports, because one person’s trades bunch into the same stock and weeks, and needs trades in at least four different years; the p-value comes from the t distribution with that number of years (with four years, a t of 2 has p = 0.14). “Some evidence” means p under 5%, “strong evidence” p under 1% over at least six years.

Companies traded

CompanyTitle on the latest filingPurchasesSalesFirst reportLatest report
Power Integrations Inc POWI VP Corporate Development085August 17, 2010April 4, 2025

Trades and what followed

Moves are against the S&P 500; green means the trade went the insider’s way.

ReportedTradedCompanyTradeValue3 months after report12 months after report12 months after trade
April 4, 2025April 2, 2025 POWI Sale $55,368 +10.7%−7.9%−15.9%
February 13, 2025February 11, 2025 POWI Sale $49,547 −6.9%−35.4%−32.4%
February 11, 2025February 10, 2025 POWI Sale $65,609 −4.6%−32.9%−30.8%
February 6, 2025February 4, 2025 POWI Sale $150,174 −3.2%−38.6%−35.4%
November 29, 2024November 27, 2024 POWI Sale $643,600 −6.0%−59.3%−60.7%
April 3, 2024April 2, 2024 POWI Sale $75,668 −4.7%−35.2%−38.8%
February 14, 2024February 12, 2024 POWI Sale $122,219 −2.7%−37.4%−47.1%
February 8, 2024February 7, 2024 POWI Sale $164,073 −11.5%−48.6%−45.1%
September 5, 2023August 31, 2023 POWI Sale $839,900 −11.0%−52.4%−49.5%
April 5, 2023April 4, 2023 POWI Sale $126,458 +10.0%−36.3%−42.4%
February 15, 2023February 14, 2023 POWI Sale $112,623 +0.5%−34.6%−32.8%
February 9, 2023February 8, 2023 POWI Sale $71,467 −6.2%−34.8%−24.9%
February 8, 2023February 7, 2023 POWI Sale $74,451 −6.2%−28.5%−30.1%
February 6, 2023February 2, 2023 POWI Sale $112,058 −8.0%−30.1%−37.1%
April 5, 2022April 4, 2022 POWI Sale $136,966 +3.8%+5.1%−3.2%
February 16, 2022February 14, 2022 POWI Sale $314,579 +0.8%−3.1%+4.3%
February 9, 2022February 7, 2022 POWI Sale $566,286 +5.0%+4.6%+6.8%
February 4, 2022February 2, 2022 POWI Sale $50,970 +7.3%+6.8%+19.8%
April 7, 2021April 5, 2021 POWI Sale $127,414 −6.4%−9.4%−3.8%
February 18, 2021February 16, 2021 POWI Sale $345,469 −23.6%−16.8%−19.8%
February 9, 2021February 5, 2021 POWI Sale $277,685 −21.1%−17.5%−20.3%
February 5, 2021February 3, 2021 POWI Sale $122,479 −18.1%−19.8%−22.9%
April 6, 2020April 2, 2020 POWI Sale $61,241 +13.0%+23.8%+41.1%
February 20, 2020February 18, 2020 POWI Sale $825,120 +19.8%+70.8%+63.9%
February 18, 2020February 14, 2020 POWI Sale $102,644 +17.9%+63.3%+56.4%
February 18, 2020February 13, 2020 POWI Sale $71,146 +17.9%+63.3%+53.1%
February 10, 2020February 7, 2020 POWI Sale $105,422 +12.3%+48.1%+50.9%
February 6, 2020February 4, 2020 POWI Sale $28,860 +15.5%+50.9%+47.0%
January 30, 2020January 28, 2020 POWI Sale $122,871 +10.3%+55.4%+51.8%
November 27, 2019November 26, 2019 POWI Sale $468,850 +1.7%+39.8%+31.7%
August 1, 2019July 30, 2019 POWI Sale $866,200 −1.2%+23.3%+26.0%
May 2, 2019May 1, 2019 POWI Sale $787,600 +11.2%+23.4%+30.3%
April 2, 2019April 2, 2019 POWI Sale $53,617 +5.3%+24.5%+29.0%
February 14, 2019February 12, 2019 POWI Sale $572,962 −6.7%+20.3%+31.9%
February 6, 2019February 4, 2019 POWI Sale $43,296 +5.4%+28.8%+27.2%
January 30, 2019January 28, 2019 POWI Sale $104,288 +12.5%+27.8%+28.3%
September 4, 2018August 31, 2018 POWI Sale $143,741 −8.4%+20.1%+16.0%
April 4, 2018April 2, 2018 POWI Sale $50,981 +8.6%−1.2%−5.7%
February 20, 2018February 15, 2018 POWI Sale $167,054 +10.7%+7.5%+7.0%
February 7, 2018February 5, 2018 POWI Sale $43,631 +9.6%+3.1%+2.9%
January 31, 2018January 30, 2018 POWI Sale $40,524 −2.3%−8.2%−10.7%
January 30, 2018January 29, 2018 POWI Sale $120,574 −1.5%−7.6%−10.4%
November 7, 2017November 3, 2017 POWI Sale $12,734 −24.0%−37.7%−34.4%
February 23, 2017February 21, 2017 POWI Sale $1,169,124 −0.2%−14.4%−16.3%
February 14, 2017February 13, 2017 POWI Sale $53,624 −2.5%−19.5%−22.5%
February 13, 2017February 10, 2017 POWI Sale $162,907 +0.5%−20.0%−21.7%
February 10, 2017February 9, 2017 POWI Sale $1,017,033 −1.8%−22.5%−20.6%
February 6, 2017February 2, 2017 POWI Sale $149,832 −6.9%−20.1%−18.0%
February 2, 2017February 1, 2017 POWI Sale $39,844 −10.8%−20.3%−20.7%
January 31, 2017January 30, 2017 POWI Sale $55,353 −18.2%−20.7%−16.5%
January 30, 2017January 27, 2017 POWI Sale $60,734 −15.2%−20.3%−18.5%
January 26, 2017January 24, 2017 POWI Sale $83,331 −13.3%−18.5%−15.6%
November 4, 2016November 2, 2016 POWI Sale $1,563,259 −3.7%+1.6%+3.7%
November 3, 2016November 1, 2016 POWI Sale $788,836 −5.5%+3.6%+4.0%
May 12, 2016May 10, 2016 POWI Sale $26,326 +16.1%+26.3%+24.7%
February 5, 2016February 5, 2016 POWI Sale $10,778 −1.0%+33.7%+29.7%
February 2, 2016February 1, 2016 POWI Sale $25,674 −2.0%+25.4%+33.2%
January 28, 2016January 28, 2016 POWI Sale $32,863 −4.4%+30.7%+39.0%
May 13, 2015May 11, 2015 POWI Sale $28,278 −22.9%−6.8%−6.3%
May 7, 2015May 6, 2015 POWI Sale $27,525 −20.2%−5.9%−8.0%
February 3, 2015January 30, 2015 POWI Sale $30,396 −10.3%−13.6%−7.5%
January 27, 2015January 23, 2015 POWI Sale $65,612 −12.6%−10.7%−11.0%
February 7, 2014February 6, 2014 POWI Sale $2,282,000 −18.7%−27.7%−26.6%
February 5, 2014February 4, 2014 POWI Sale $115,097 −21.0%−26.6%−23.2%
January 24, 2014January 23, 2014 POWI Sale $75,123 −5.8%−24.5%−26.3%
August 12, 2013August 9, 2013 POWI Sale $417,585 −0.5%−11.9%−10.3%
August 7, 2013August 6, 2013 POWI Sale $1,976,980 +3.4%−10.8%−11.3%
May 10, 2013May 9, 2013 POWI Sale $33,795 +19.2%+0.1%−1.8%
May 8, 2013May 6, 2013 POWI Sale $67,334 +18.5%−1.8%−4.7%
February 14, 2013February 12, 2013 POWI Sale $592,820 −7.9%+16.4%+19.0%
February 13, 2013February 11, 2013 POWI Sale $516,480 −8.0%+15.9%+17.7%
February 8, 2013February 7, 2013 POWI Sale $584,319 −7.9%+17.7%+12.9%
May 10, 2012May 8, 2012 POWI Sale $2,164,504 −25.6%−20.8%−20.2%
May 4, 2012May 4, 2012 POWI Sale $20,729 −14.5%−19.9%−18.0%
February 29, 2012February 28, 2012 POWI Sale $903,535 +15.0%−0.2%−4.7%
February 8, 2012February 7, 2012 POWI Sale $1,812,201 +10.0%−1.5%+2.5%
November 9, 2011November 8, 2011 POWI Sale $361,500 −2.6%−27.7%−26.3%
September 1, 2011August 31, 2011 POWI Sale $322,200 +13.0%−5.8%−10.5%
May 6, 2011May 4, 2011 POWI Sale $20,635 −6.6%+10.5%−4.4%
February 11, 2011February 10, 2011 POWI Sale $135,177 −11.0%−13.4%−12.6%
November 24, 2010November 22, 2010 POWI Sale $534,321 −13.6%−19.6%−14.8%
November 23, 2010November 19, 2010 POWI Sale $36,110 −10.5%−18.2%−12.6%
November 23, 2010November 18, 2010 POWI Sale $658,314 −10.5%−18.2%−13.4%
November 2, 2010November 1, 2010 POWI Sale $47,403 −5.5%−6.8%−4.0%
August 17, 2010August 13, 2010 POWI Sale $100,384 +15.3%−9.9%−6.9%

Open-market purchases and sales of at least $10,000 in companies we cover, from SEC Form 4 filings; sales made under a pre-set Rule 10b5-1 plan are not shown. “Not yet” means the window has not finished or the share price was under $5 at entry. These are the shares’ moves after each trade: they say nothing about why Walker Clifford traded and do not suggest the use of non-public information. How every insider compares · the insider trading backtest.