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Lambert Michael D: insider trades

Director at Western Digital. No open-market purchases and 9 sales not made under a pre-set plan, reported from December 21, 2012 to May 16, 2018.

What happened after Lambert Michael D’s sales?

After their sales, the shares moved −4.4% against the index over 12 months on average (a negative figure means selling was the right call); 56% 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

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 9 +2.2% +8.1% 33% 5 −0.29 0.78 No reliable evidence
Sales, 12 months after the report 9 −4.4% −20.4% 56% 5 −0.30 0.78 No reliable evidence
Sales, 12 months after the trade 9 −3.8% −20.7% 56% 5 −0.29 0.79 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
Western Digital WDC —09December 21, 2012May 16, 2018

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
May 16, 2018May 16, 2018 WDC Sale $991,227 −29.2%−56.0%−53.7%
November 3, 2017November 1, 2017 WDC Sale $94,990 −8.1%−51.1%−54.0%
November 24, 2014November 20, 2014 WDC Sale $506,000 +2.3%−41.7%−41.9%
November 18, 2014November 18, 2014 WDC Sale $500,650 +8.1%−40.2%−38.2%
August 25, 2014August 21, 2014 WDC Sale $1,440,510 −2.7%−20.4%−20.7%
November 14, 2013November 12, 2013 WDC Sale $718,500 +11.3%+16.8%+20.0%
May 10, 2013May 9, 2013 WDC Sale $1,382,295 +14.3%+26.3%+26.5%
February 15, 2013February 14, 2013 WDC Sale $1,059,312 +13.6%+57.1%+57.4%
December 21, 2012December 20, 2012 WDC Sale $482,673 +10.3%+69.7%+70.2%

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