undamentalytics Newsletter

Leproust Emily M.: insider trades

Chief executive at Twist Bioscience Corp. No open-market purchases and 53 sales not made under a pre-set plan, reported from September 9, 2020 to September 23, 2026.

What happened after Leproust Emily M.’s sales?

After their sales, the shares moved +61.7% against the index over 12 months on average (a negative figure means selling was the right call); 61% 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

Leproust Emily M.: 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 49 +13.7% +6.8% 43% 5 1.00 0.37 No reliable evidence
Sales, 12 months after the report 36 +61.7% −9.5% 61% 4 0.51 0.65 No reliable evidence
Sales, 12 months after the trade 37 +64.5% −11.8% 51% 4 0.44 0.69 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
Twist Bioscience Corp TWST Chief Executive Officer053September 9, 2020September 23, 2026

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 23, 2026September 21, 2026 TWST Sale $279,182 not yetnot yetnot yet
September 10, 2026September 8, 2026 TWST Sale $282,271 not yetnot yetnot yet
August 25, 2026August 21, 2026 TWST Sale $923,286 not yetnot yetnot yet
August 5, 2026August 3, 2026 TWST Sale $435,217 not yetnot yetnot yet
June 24, 2026June 22, 2026 TWST Sale $147,396 +85.7%not yetnot yet
June 10, 2026June 8, 2026 TWST Sale $158,188 +67.9%not yetnot yet
May 26, 2026May 21, 2026 TWST Sale $366,855 +131.5%not yetnot yet
May 6, 2026May 4, 2026 TWST Sale $293,008 +91.6%not yetnot yet
March 24, 2026March 20, 2026 TWST Sale $76,282 +86.6%not yetnot yet
March 10, 2026March 6, 2026 TWST Sale $112,500 +37.1%not yetnot yet
February 25, 2026February 23, 2026 TWST Sale $336,546 +31.9%not yetnot yet
February 5, 2026February 3, 2026 TWST Sale $232,947 +8.4%not yetnot yet
December 23, 2025December 22, 2025 TWST Sale $55,469 +40.5%not yetnot yet
December 10, 2025December 8, 2025 TWST Sale $74,144 +42.8%not yetnot yet
November 25, 2025November 21, 2025 TWST Sale $70,570 +43.5%not yetnot yet
November 5, 2025November 3, 2025 TWST Sale $156,775 +51.1%not yetnot yet
November 3, 2025October 30, 2025 TWST Sale $986,556 +56.0%not yet+301.5%
October 8, 2025October 6, 2025 TWST Sale $1,009,092 +7.0%+359.0%+371.7%
October 6, 2025October 2, 2025 TWST Sale $13,880 +14.1%+371.7%+551.2%
September 24, 2025September 22, 2025 TWST Sale $46,962 +20.3%+553.8%+453.6%
September 10, 2025September 8, 2025 TWST Sale $58,346 +23.2%+409.2%+359.4%
August 25, 2025August 21, 2025 TWST Sale $70,507 +1.9%+431.5%+410.5%
August 6, 2025August 4, 2025 TWST Sale $158,391 +18.6%+375.9%+257.4%
July 7, 2025July 2, 2025 TWST Sale $17,226 −22.4%+130.8%+142.8%
June 24, 2025June 20, 2025 TWST Sale $60,005 −36.1%+148.5%+120.6%
June 10, 2025June 6, 2025 TWST Sale $68,898 −36.8%+91.9%+97.5%
May 23, 2025May 21, 2025 TWST Sale $83,360 −15.2%+105.6%+83.4%
May 7, 2025May 5, 2025 TWST Sale $189,831 −34.5%+40.0%+34.0%
April 4, 2025April 2, 2025 TWST Sale $19,055 −18.3%−4.3%+15.9%
March 24, 2025March 20, 2025 TWST Sale $71,940 −22.2%−7.7%−11.8%
March 10, 2025March 6, 2025 TWST Sale $98,266 −20.8%−11.3%+3.5%
February 25, 2025February 21, 2025 TWST Sale $123,262 −30.6%−3.2%+1.6%
February 5, 2025February 3, 2025 TWST Sale $256,620 −32.7%−27.4%−24.9%
January 7, 2025January 3, 2025 TWST Sale $24,892 −8.1%−35.0%−40.6%
December 26, 2024December 20, 2024 TWST Sale $74,265 −13.7%−50.1%−48.1%
December 10, 2024December 6, 2024 TWST Sale $116,783 −7.0%−49.8%−52.3%
November 13, 2024November 11, 2024 TWST Sale $382,464 +19.5%−45.9%−50.4%
November 8, 2024November 6, 2024 TWST Sale $639,440 −3.0%−50.4%−48.5%
November 6, 2024November 4, 2024 TWST Sale $201,192 −0.5%−47.3%−46.2%
October 4, 2024October 2, 2024 TWST Sale $587,872 +4.2%−44.0%−45.9%
September 24, 2024September 20, 2024 TWST Sale $81,206 +1.2%−58.7%−59.6%
September 10, 2024September 6, 2024 TWST Sale $91,634 +7.2%−62.7%−56.4%
August 7, 2024August 5, 2024 TWST Sale $205,200 −11.7%−62.2%−68.6%
July 5, 2024July 2, 2024 TWST Sale $53,472 −15.0%−35.5%−39.3%
June 24, 2024June 20, 2024 TWST Sale $85,578 −8.0%−39.1%−39.1%
June 10, 2024June 6, 2024 TWST Sale $123,603 −17.6%−47.6%−49.2%
May 7, 2024May 3, 2024 TWST Sale $154,572 +6.8%−34.6%−31.6%
April 4, 2024April 2, 2024 TWST Sale $37,062 +42.7%+10.9%+9.2%
March 22, 2024March 20, 2024 TWST Sale $37,811 +34.6%+11.0%+15.2%
March 8, 2024March 6, 2024 TWST Sale $55,658 +30.6%−3.1%−15.0%
February 17, 2021February 12, 2021 TWST Sale $335,278 −43.1%−76.6%−80.3%
February 11, 2021February 9, 2021 TWST Sale $13,239,935 −51.2%−80.3%−82.8%
September 9, 2020September 4, 2020 TWST Sale $6,298,496 +112.9%+57.2%+47.0%

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