undamentalytics Newsletter

Jacobson Matthew: insider trades

Director, 10% owner at 4 companies we cover. 14 open-market purchases and 28 sales not made under a pre-set plan, reported from December 8, 2020 to August 17, 2026.

Would copying Jacobson Matthew’s purchases have beaten the S&P 500?

Too few purchases to judge. Only 14 purchases have 12 months of prices after the report; we judge insiders once they have 20. The figures below can swing a long way on a handful of trades. Buying each purchase the day after it was reported, an equal amount each, and holding it 12 months or until they reported a sale would have turned $10,000 on December 14, 2021 into $8,743 by November 2, 2026, −2.7% a year. The copy held shares only 37% of the time, so the fair comparison is the S&P 500 on those same days with Treasury bills otherwise: $10,975, +1.9% a year (the S&P 500 held throughout made $17,455, +12.1% a year). Beta against the index was 1.16. Twelve months after each report, the average purchase was +7.2% against the S&P 500 (median +8.1%), and 71% beat it. Measured from the trade date, the insider’s own timing, the average was +13.2%. After their sales, the shares moved −8.2% against the index over 12 months on average (a negative figure means selling was the right call); 68% 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.

$0$5.0k$10.0k$15.0k 202120222023202420252026 $17.5k$11.0k$8.7k
Copying Jacobson MatthewS&P 500, same days investedS&P 500, held throughout $10,000 copying Jacobson Matthew’s open-market purchases from December 14, 2021, before costs and taxes, marked weekly. Each purchase gets the same starting stake, bought at the close of the first trading day after the report and sold 12 months later or the day after a reported sale of that stock; uninvested money earns the Treasury bill rate. “Same days invested” holds the S&P 500 only on the days the copy held shares, Treasury bills otherwise.
Return a year, copying
−2.7%
S&P 500, same days invested
+1.9% (held throughout +12.1%)
Time in shares
37%
Sharpe ratio (S&P 500)
0.08 (0.51)
Biggest drop (S&P 500)
−68% (−25%)
Market sensitivity (beta)
1.16
Purchases copied
14

Trade by trade

Jacobson Matthew: trades against the S&P 500 afterwards
MeasuredTrades countedAverage vs S&P 500MedianWent the right wayYearst-statisticp-valueEvidence
Purchases, 3 months after the report 14 −17.4% −26.3% 29% 2 — — Not enough years
Purchases, 6 months after the report 14 −8.1% −17.4% 36% 2 — — Not enough years
Purchases, 12 months after the report 14 +7.2% +8.1% 71% 2 — — Not enough years
Purchases, 12 months after the trade 14 +13.2% +14.7% 71% 2 — — Not enough years
Sales, 3 months after the report 27 −4.1% −5.5% 63% 6 −0.77 0.48 No reliable evidence
Sales, 12 months after the report 22 −8.2% −14.3% 68% 5 −0.19 0.86 No reliable evidence
Sales, 12 months after the trade 22 −5.8% −12.3% 64% 5 −0.08 0.94 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
Datadog, Inc. DDOG —416December 8, 2020August 17, 2026
Gitlab Inc. GTLB —211December 13, 2021March 23, 2026
Braze, Inc. BRZE —80April 8, 2022October 5, 2022
Procore Technologies, Inc. PCOR —01June 17, 2025June 17, 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
August 17, 2026August 13, 2026 DDOG Sale $14,999,880 not yetnot yetnot yet
June 2, 2026May 29, 2026 DDOG Sale $9,999,629 −18.1%not yetnot yet
May 12, 2026May 8, 2026 DDOG Sale $9,999,922 +17.8%not yetnot yet
March 23, 2026March 19, 2026 GTLB Sale $26,353,205 +24.3%not yetnot yet
December 23, 2025December 19, 2025 GTLB Sale $12,750,212 −37.8%not yetnot yet
November 13, 2025November 10, 2025 DDOG Sale $87,066,603 −36.6%not yetnot yet
September 25, 2025September 23, 2025 GTLB Sale $3,189,524 −24.9%−18.3%−17.4%
September 23, 2025September 19, 2025 GTLB Sale $11,708,775 −24.8%−18.8%−20.5%
September 19, 2025September 17, 2025 GTLB Sale $22,386,329 −25.6%−17.3%−19.5%
September 10, 2025September 8, 2025 GTLB Sale $6,701,994 −23.4%−18.0%−22.1%
August 28, 2025August 26, 2025 DDOG Sale $87,105,990 +10.8%+44.4%+71.5%
August 26, 2025August 22, 2025 DDOG Sale $14,196,226 +16.0%+59.6%+49.9%
June 27, 2025June 25, 2025 GTLB Sale $5,476,208 −3.9%−52.1%−53.1%
June 17, 2025June 13, 2025 PCOR Sale $20,020,746 −1.6%−67.6%−62.0%
May 9, 2025May 7, 2025 DDOG Sale $25,169,764 +3.1%+52.2%+55.8%
March 26, 2025March 24, 2025 GTLB Sale $8,001,291 −18.8%−71.3%−76.1%
December 30, 2024December 26, 2024 GTLB Sale $32,713,308 −16.4%−52.2%−51.7%
November 20, 2024November 18, 2024 DDOG Sale $3,150,250 −21.7%−4.6%+14.4%
November 13, 2024November 11, 2024 DDOG Sale $6,630,352 −5.6%+21.7%+38.4%
September 13, 2024September 11, 2024 DDOG Sale $1,000,111 +29.7%+3.7%+5.9%
June 17, 2024June 13, 2024 DDOG Sale $2,200,961 −5.5%0.0%−7.1%
September 22, 2023September 20, 2023 GTLB Sale $4,313,491 +34.1%−15.9%−21.5%
September 15, 2023September 13, 2023 GTLB Sale $4,201,058 +23.4%−21.5%−20.7%
August 31, 2023August 29, 2023 DDOG Sale $2,100,276 +19.3%−12.6%−3.3%
August 16, 2023August 14, 2023 DDOG Sale $4,428,339 +17.8%−0.2%+4.1%
June 16, 2023June 14, 2023 DDOG Sale $6,432,265 −5.5%−6.4%−3.6%
December 7, 2022December 5, 2022 DDOG Purchase $13,326,435 −8.2%+36.6%+47.1%
December 2, 2022November 30, 2022 DDOG Purchase $1,387,415 +2.2%+47.1%+42.1%
November 14, 2022November 9, 2022 DDOG Purchase $19,999,441 −7.1%+12.0%+34.6%
November 9, 2022November 7, 2022 DDOG Purchase $49,998,486 +2.4%+23.0%+27.0%
October 5, 2022October 3, 2022 BRZE Purchase $32,301 −40.1%+4.4%+7.0%
October 4, 2022September 15, 2022 BRZE Purchase $441,678 −39.0%+4.7%+15.0%
October 3, 2022September 29, 2022 BRZE Purchase $16,967,862 −35.5%+4.7%+14.7%
September 26, 2022September 22, 2022 BRZE Purchase $3,763,998 −31.7%+18.5%+18.5%
September 22, 2022September 20, 2022 BRZE Purchase $1,295,699 −27.9%+14.1%+12.7%
September 20, 2022September 16, 2022 BRZE Purchase $14,499,153 −24.6%+11.5%+14.6%
April 12, 2022April 8, 2022 BRZE Purchase $1,450,426 +13.4%−18.9%−1.0%
April 8, 2022April 6, 2022 BRZE Purchase $13,548,716 +25.1%−8.9%−2.1%
March 7, 2022March 3, 2022 DDOG Sale $25,377,976 −15.2%−40.6%−42.8%
December 14, 2021December 10, 2021 GTLB Purchase $24,999,820 −33.9%−24.6%−20.4%
December 13, 2021December 9, 2021 GTLB Purchase $50,001,048 −39.0%−23.1%−25.3%
December 8, 2020December 8, 2020 DDOG Sale $141,264 −21.1%+54.5%+54.8%

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