undamentalytics Newsletter

Mapes Michelle: insider trades

Officer at Green Plains Inc. No open-market purchases and 25 sales not made under a pre-set plan, reported from February 22, 2013 to September 24, 2025.

What happened after Mapes Michelle’s sales?

After their sales, the shares moved −4.3% against the index over 12 months on average (a negative figure means selling was the right call); 72% 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

Mapes Michelle: 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 25 +0.2% −1.4% 52% 10 0.71 0.49 No reliable evidence
Sales, 12 months after the report 25 −4.3% −24.0% 72% 10 0.52 0.61 No reliable evidence
Sales, 12 months after the trade 25 −7.5% −23.3% 72% 10 0.40 0.70 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
Green Plains Inc. GPRE Chief Legal and Admin Officer025February 22, 2013September 24, 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
September 24, 2025September 22, 2025 GPRE Sale $294,373 +3.9%+43.4%+44.9%
May 24, 2023May 23, 2023 GPRE Sale $98,340 −5.7%−71.7%−71.2%
May 15, 2023May 12, 2023 GPRE Sale $155,500 −1.4%−66.0%−64.9%
May 10, 2023May 8, 2023 GPRE Sale $939,300 +1.0%−62.3%−63.9%
June 17, 2021June 15, 2021 GPRE Sale $61,650 +4.4%+7.2%+11.9%
May 7, 2021May 5, 2021 GPRE Sale $313,000 +15.8%−1.4%−6.8%
June 19, 2020June 18, 2020 GPRE Sale $50,450 +36.6%+183.7%+167.4%
December 20, 2019December 19, 2019 GPRE Sale $32,680 −44.3%−31.4%−38.4%
November 22, 2019November 21, 2019 GPRE Sale $77,000 −17.2%−12.2%−19.1%
March 21, 2019March 19, 2019 GPRE Sale $85,590 −39.9%−55.7%−62.5%
March 15, 2019March 13, 2019 GPRE Sale $80,800 −28.1%−60.9%−59.6%
November 20, 2018November 16, 2018 GPRE Sale $119,980 −11.5%−26.0%−27.4%
February 28, 2018February 26, 2018 GPRE Sale $134,890 +13.2%−20.0%−19.4%
June 7, 2017June 5, 2017 GPRE Sale $162,530 −18.1%−24.0%−23.3%
May 15, 2017May 15, 2017 GPRE Sale $57,088 −25.4%−31.9%−32.0%
May 12, 2017May 10, 2017 GPRE Sale $102,000 −24.7%−32.0%−39.7%
March 1, 2017February 27, 2017 GPRE Sale $98,000 −9.7%−34.0%−37.1%
December 21, 2016December 19, 2016 GPRE Sale $58,540 −24.8%−61.3%−62.0%
December 2, 2016December 1, 2016 GPRE Sale $82,080 −27.6%−60.8%−59.4%
June 24, 2016June 23, 2016 GPRE Sale $58,500 +37.7%−9.0%−15.1%
March 7, 2016March 4, 2016 GPRE Sale $45,570 +37.5%+36.5%+33.6%
March 24, 2014March 20, 2014 GPRE Sale $309,000 +4.3%−20.4%−22.5%
December 6, 2013December 4, 2013 GPRE Sale $85,750 +54.6%+28.0%+38.3%
March 14, 2013March 12, 2013 GPRE Sale $51,600 +18.4%+129.9%+104.3%
February 22, 2013February 22, 2013 GPRE Sale $77,600 +55.4%+144.3%+135.2%

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 Mapes Michelle traded and do not suggest the use of non-public information. How every insider compares · the insider trading backtest.