undamentalytics Newsletter

667, L.P.: insider trades

Director at 7 companies we cover. 14 open-market purchases and no sales not made under a pre-set plan, reported from May 17, 2013 to September 30, 2026.

Would copying 667, L.P.’s purchases have beaten the S&P 500?

Too few purchases to judge. Only 12 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 May 20, 2013 into $18,336 by November 2, 2026, +4.6% a year. The copy held shares only 65% of the time, so the fair comparison is the S&P 500 on those same days with Treasury bills otherwise: $30,014, +8.5% a year (the S&P 500 held throughout made $56,953, +13.8% a year). Beta against the index was 0.71. Twelve months after each report, the average purchase was +0.4% against the S&P 500 (median +2.2%), and 50% beat it. Measured from the trade date, the insider’s own timing, the average was +7.1%.

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 2013201520172019202120232025 $57.0k$30.0k$18.3k
Copying 667, L.P.S&P 500, same days investedS&P 500, held throughout $10,000 copying 667, L.P.’s open-market purchases from May 20, 2013, 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
+4.6%
S&P 500, same days invested
+8.5% (held throughout +13.8%)
Time in shares
65%
Sharpe ratio (S&P 500)
0.29 (0.74)
Biggest drop (S&P 500)
−74% (−34%)
Market sensitivity (beta)
0.71
Purchases copied
13

Trade by trade

667, L.P.: trades against the S&P 500 afterwards
MeasuredTrades countedAverage vs S&P 500MedianWent the right wayYearst-statisticp-valueEvidence
Purchases, 3 months after the report 12 +2.9% +2.0% 58% 8 0.70 0.51 No reliable evidence
Purchases, 6 months after the report 12 +4.7% −2.0% 42% 8 1.11 0.30 No reliable evidence
Purchases, 12 months after the report 12 +0.4% +2.2% 50% 8 0.16 0.88 No reliable evidence
Purchases, 12 months after the trade 12 +7.1% +5.5% 58% 8 0.70 0.50 No reliable evidence
Sales, 3 months after the report 0 — — — — — — Not enough years
Sales, 12 months after the report 0 — — — — — — Not enough years
Sales, 12 months after the trade 0 — — — — — — Not enough years

“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
Acadia Pharmaceuticals Inc ACAD —40May 17, 2013May 24, 2023
Incyte INCY —40February 16, 2016March 10, 2022
Kodiak Sciences Inc. KOD —20August 19, 2021September 30, 2026
Neurogene Inc. NGNE —10December 20, 2019December 20, 2019
Tscan Therapeutics, Inc. TCRX —10May 12, 2022May 12, 2022
Madrigal Pharmaceuticals, Inc. MDGL —10December 14, 2023December 14, 2023
Immunocore Holdings plc IMCR —10March 19, 2025March 19, 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 30, 2026September 28, 2026 KOD Purchase $63,398,971 not yetnot yetnot yet
March 19, 2025March 17, 2025 IMCR Purchase $23,992,063 −2.7%−17.8%−18.0%
December 14, 2023December 12, 2023 MDGL Purchase $7,548,577 +1.8%−0.9%+4.2%
May 24, 2023May 22, 2023 ACAD Purchase $22,706,368 +10.5%−67.9%−64.6%
May 12, 2022May 10, 2022 TCRX Purchase $2,558,794 not yetnot yetnot yet
March 10, 2022March 8, 2022 INCY Purchase $28,108,516 +2.1%+5.3%+6.8%
December 17, 2021December 15, 2021 INCY Purchase $115,556,256 +7.1%+25.4%+30.2%
August 19, 2021August 17, 2021 KOD Purchase $10,009,624 +3.7%−83.3%−84.5%
December 20, 2019December 20, 2019 NGNE Purchase $25,347,353 −5.0%−24.5%−10.5%
September 24, 2018September 20, 2018 ACAD Purchase $22,650,075 −11.2%+70.9%+113.7%
August 12, 2016August 10, 2016 ACAD Purchase $42,999,990 −11.5%−17.0%−17.0%
February 26, 2016February 24, 2016 INCY Purchase $4,551,089 +5.8%+56.3%+39.1%
February 16, 2016February 12, 2016 INCY Purchase $61,981,579 −5.3%+38.0%+49.8%
May 17, 2013May 15, 2013 ACAD Purchase $24,912,500 +39.4%+19.9%+35.9%

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 667, L.P. traded and do not suggest the use of non-public information. How every insider compares · the insider trading backtest.