undamentalytics Newsletter

Rock Jennifer: insider trades

Chief financial officer, Officer at Zillow Group, Inc. No open-market purchases and 45 sales not made under a pre-set plan, reported from August 29, 2018 to August 17, 2026.

What happened after Rock Jennifer’s sales?

After their sales, the shares moved +18.9% against the index over 12 months on average (a negative figure means selling was the right call); 44% 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

Rock Jennifer: 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 44 +2.9% +4.4% 46% 9 0.77 0.46 No reliable evidence
Sales, 12 months after the report 41 +18.9% +11.4% 44% 8 0.66 0.53 No reliable evidence
Sales, 12 months after the trade 41 +19.5% +14.6% 44% 8 0.69 0.51 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
Zillow Group, Inc. Z Chief Accounting Officer045August 29, 2018August 17, 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
August 17, 2026August 13, 2026 Z Sale $33,898 not yetnot yetnot yet
May 15, 2026May 14, 2026 Z Sale $39,286 −11.2%not yetnot yet
February 13, 2026February 12, 2026 Z Sale $95,692 −23.9%not yetnot yet
November 12, 2025November 10, 2025 Z Sale $434,126 −39.4%not yetnot yet
August 15, 2025August 13, 2025 Z Sale $253,402 −23.3%−77.6%−80.7%
August 11, 2025August 7, 2025 Z Sale $428,086 −15.2%−77.6%−83.7%
May 16, 2025May 14, 2025 Z Sale $195,126 +15.3%−72.2%−72.1%
May 12, 2025May 8, 2025 Z Sale $408,156 +10.5%−75.8%−72.8%
February 14, 2025February 12, 2025 Z Sale $597,071 −13.4%−56.7%−58.8%
December 9, 2024December 6, 2024 Z Sale $251,072 −7.6%−23.4%−22.6%
November 26, 2024November 22, 2024 Z Sale $100,303 −9.6%−30.8%−26.7%
November 15, 2024November 13, 2024 Z Sale $836,689 −0.2%−20.9%−21.2%
August 21, 2024August 19, 2024 Z Sale $199,692 +38.9%+42.5%+31.4%
August 16, 2024August 14, 2024 Z Sale $169,515 +26.4%+31.4%+37.8%
August 12, 2024August 8, 2024 Z Sale $199,382 +31.1%+39.2%+39.7%
May 17, 2024May 15, 2024 Z Sale $116,609 +20.8%+39.2%+36.5%
February 16, 2024February 14, 2024 Z Sale $421,162 −26.4%+17.6%+14.6%
December 6, 2023December 6, 2023 Z Sale $100,412 +9.8%+41.8%+46.9%
November 16, 2023November 15, 2023 Z Sale $237,461 +26.8%+59.8%+48.1%
August 18, 2023August 16, 2023 Z Sale $190,002 −23.4%−18.0%−23.9%
August 7, 2023August 3, 2023 Z Sale $611,836 −32.1%−32.9%−39.0%
May 19, 2023May 17, 2023 Z Sale $96,606 +4.9%−36.9%−32.8%
May 5, 2023May 4, 2023 Z Sale $390,428 +8.6%−40.8%−39.9%
February 17, 2023February 15, 2023 Z Sale $395,862 −1.1%−6.9%−7.1%
December 5, 2022December 2, 2022 Z Sale $99,684 +6.7%+8.4%+0.5%
November 18, 2022November 16, 2022 Z Sale $139,507 +21.6%−0.7%−10.0%
November 7, 2022November 3, 2022 Z Sale $295,916 +23.9%−6.1%−5.5%
August 19, 2022August 17, 2022 Z Sale $126,995 +11.8%+44.5%+37.9%
May 19, 2022May 18, 2022 Z Sale $80,978 −26.9%+3.2%+1.0%
February 18, 2022February 16, 2022 Z Sale $79,191 −21.9%−22.5%−21.0%
November 19, 2021November 17, 2021 Z Sale $116,186 +11.9%−22.1%−23.6%
May 18, 2020May 14, 2020 Z Sale $42,329 +44.6%+68.4%+87.2%
February 26, 2020February 24, 2020 Z Sale $549,572 +2.6%+165.1%+160.5%
February 20, 2020February 18, 2020 Z Sale $37,598 −5.6%+142.7%+244.3%
December 4, 2019December 3, 2019 Z Sale $150,000 +21.2%+139.8%+145.8%
November 19, 2019November 19, 2019 Z Sale $176,253 +49.3%+164.3%+154.1%
November 15, 2019November 14, 2019 Z Sale $24,256 +50.8%+145.7%+154.3%
August 19, 2019August 15, 2019 Z Sale $227,566 +5.7%+120.2%+101.8%
June 5, 2019June 3, 2019 Z Sale $106,800 −37.2%+11.4%+26.6%
May 21, 2019May 20, 2019 Z Sale $79,472 −18.8%+22.8%+21.6%
May 17, 2019May 15, 2019 Z Sale $190,330 −14.3%+21.6%+21.1%
February 27, 2019February 26, 2019 Z Sale $685,874 +4.0%+25.2%+21.8%
February 19, 2019February 14, 2019 Z Sale $15,720 +16.1%+59.4%+18.8%
November 21, 2018November 20, 2018 Z Sale $11,693 +35.2%+17.7%+21.1%
August 29, 2018August 28, 2018 Z Sale $20,202 −18.5%−33.7%−32.2%

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