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Garnreiter Michael: insider trades

Director at 3 companies we cover. No open-market purchases and 10 sales not made under a pre-set plan, reported from February 14, 2011 to June 4, 2025.

What happened after Garnreiter Michael’s sales?

After their sales, the shares moved −37.2% against the index over 12 months on average (a negative figure means selling was the right call); 90% 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

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 10 −3.4% −8.3% 70% 7 −0.55 0.60 No reliable evidence
Sales, 12 months after the report 10 −37.2% −35.4% 90% 7 −2.95 0.025 Some evidence: seller right
Sales, 12 months after the trade 10 −36.8% −37.6% 90% 7 −3.01 0.024 Some evidence: seller right

“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
Knight-swift Transportation Holdings Inc. KNX —05November 15, 2017August 21, 2024
Amtech Systems Inc ASYS —03February 14, 2011December 15, 2017
Axon Enterprise AXON —02November 13, 2014June 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
June 4, 2025June 3, 2025 AXON Sale $4,560,000 −17.1%−66.3%−60.9%
August 21, 2024August 13, 2024 KNX Sale $101,140 −1.5%−33.2%−37.9%
February 28, 2022February 25, 2022 KNX Sale $108,740 −5.7%+15.8%+13.6%
September 9, 2020September 9, 2020 KNX Sale $236,250 −19.1%−21.3%−22.8%
December 15, 2017December 13, 2017 ASYS Sale $50,000 −22.6%−52.6%−55.9%
December 12, 2017December 12, 2017 KNX Sale $43,000 +10.2%−37.6%−37.3%
November 15, 2017November 15, 2017 KNX Sale $96,250 +17.0%−26.1%−22.5%
November 13, 2014November 12, 2014 AXON Sale $80,000 +30.2%−16.6%−10.8%
February 18, 2011February 16, 2011 ASYS Sale $100,103 −10.8%−65.4%−66.9%
February 14, 2011February 14, 2011 ASYS Sale $24,600 −14.3%−68.6%−66.9%

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