undamentalytics Newsletter

Robbins Larry: insider trades

Director, 10% owner at 4 companies we cover. 16 open-market purchases and 8 sales not made under a pre-set plan, reported from September 18, 2012 to August 17, 2026.

Would copying Robbins Larry’s purchases have beaten the S&P 500?

Too few purchases to judge. Only 11 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 September 19, 2012 into $1,757 by November 2, 2026, −11.6% a year. The copy held shares only 44% of the time, so the fair comparison is the S&P 500 on those same days with Treasury bills otherwise: $21,601, +5.6% a year (the S&P 500 held throughout made $65,907, +14.3% a year). Beta against the index was 1.05. Twelve months after each report, the average purchase was −10.9% against the S&P 500 (median −0.5%), and 46% beat it. Measured from the trade date, the insider’s own timing, the average was −3.2%. After their sales, the shares moved +20.2% against the index over 12 months on average (a negative figure means selling was the right call); 20% 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$20.0k$40.0k$60.0k 20122014201620182020202220242026 $65.9k$21.6k$1.8k
Copying Robbins LarryS&P 500, same days investedS&P 500, held throughout $10,000 copying Robbins Larry’s open-market purchases from September 19, 2012, 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
−11.6%
S&P 500, same days invested
+5.6% (held throughout +14.3%)
Time in shares
44%
Sharpe ratio (S&P 500)
−0.09 (0.78)
Biggest drop (S&P 500)
−95% (−34%)
Market sensitivity (beta)
1.05
Purchases copied
11

Trade by trade

Robbins Larry: trades against the S&P 500 afterwards
MeasuredTrades countedAverage vs S&P 500MedianWent the right wayYearst-statisticp-valueEvidence
Purchases, 3 months after the report 11 +4.0% −3.8% 36% 6 0.20 0.85 No reliable evidence
Purchases, 6 months after the report 11 +14.8% +10.4% 73% 6 0.69 0.52 No reliable evidence
Purchases, 12 months after the report 11 −10.9% −0.5% 46% 6 −0.82 0.45 No reliable evidence
Purchases, 12 months after the trade 10 −3.2% +8.5% 60% 5 −0.23 0.83 No reliable evidence
Sales, 3 months after the report 7 +0.5% −1.1% 57% 6 0.39 0.71 No reliable evidence
Sales, 12 months after the report 5 +20.2% +13.4% 20% 5 1.96 0.12 No reliable evidence
Sales, 12 months after the trade 5 +22.9% +14.8% 40% 5 1.63 0.18 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
Tenet Healthcare Corp THC —93September 18, 2012April 22, 2021
Butterfly Network, Inc. BFLY —72May 28, 2021August 17, 2026
CVS Health CVS —02May 6, 2025May 21, 2026
Flex Ltd. FLEX —01October 23, 2015October 23, 2015

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 BFLY Sale $20,626,396 not yetnot yetnot yet
August 3, 2026July 31, 2026 BFLY Sale $13,976,674 −28.6%not yetnot yet
May 21, 2026May 19, 2026 CVS Sale $317,479,377 −1.1%not yetnot yet
December 15, 2025December 11, 2025 BFLY Purchase $64,537 not yetnot yetnot yet
December 5, 2025December 3, 2025 BFLY Purchase $4,649,388 not yetnot yetnot yet
November 21, 2025November 19, 2025 BFLY Purchase $6,784,000 not yetnot yetnot yet
May 6, 2025May 2, 2025 CVS Sale $253,706,963 −16.8%+7.6%−5.2%
September 4, 2024August 30, 2024 BFLY Purchase $261,908 not yetnot yetnot yet
August 30, 2024August 28, 2024 BFLY Purchase $1,684,971 not yetnot yetnot yet
March 15, 2022March 15, 2022 BFLY Purchase $2,250,000 −23.8%−52.3%not yet
May 28, 2021May 26, 2021 BFLY Purchase $2,106,446 −11.6%−75.2%−69.6%
April 22, 2021April 21, 2021 THC Sale $170,050,150 +22.7%+27.7%+54.9%
December 15, 2020December 11, 2020 THC Sale $49,214,918 +27.7%+56.2%+56.9%
August 27, 2019August 23, 2019 THC Purchase $1,684,318 +47.0%+13.5%+10.7%
July 26, 2019July 24, 2019 THC Purchase $16,231,630 +4.0%−0.5%+14.9%
November 13, 2015November 11, 2015 THC Purchase $29,301,500 −17.0%−57.8%−62.5%
October 23, 2015October 22, 2015 THC Purchase $14,852,124 −3.8%−28.9%−23.2%
October 23, 2015October 22, 2015 FLEX Sale $222,000,000 −7.1%+13.4%+14.8%
August 7, 2015August 5, 2015 THC Purchase $38,010,539 −33.8%−55.3%−55.6%
December 23, 2013December 19, 2013 THC Purchase $25,749,397 −0.4%+12.4%+13.5%
December 19, 2013December 17, 2013 THC Purchase $40,119,316 −6.6%+11.8%+6.4%
November 14, 2013November 12, 2013 THC Sale $3,501,600 +6.5%−3.8%−7.1%
October 23, 2012October 19, 2012 THC Purchase $4,706,000 +53.9%+65.5%+72.5%
September 18, 2012September 17, 2012 THC Purchase $17,250,000 +35.8%+46.7%+60.6%

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