https://gmauthority.com/blog/2025/09/gm-ceo-mary-barra-sells-40-percent-of-her-shares/
GM Chair and CEO Mary Barra has sold 40.3 percent of her holdings in General Motors stock, offloading 372,024 shares late last month on August 28th, 2025.
Does she know something we don’t?
40% sounds a bit excessive for the usual routine portfolio rebalancing or estate planning issues.
Maybe she finally caught on to what “we” have know for some time. 
The Captain
Do we know any details? To avoid charges of insider trading execs often file a future plan to unload shares at specified intervals. They probably accumulate shares via stock options and make moves to diversify.
From the article in the OP.
Barra retains 552,238 shares valued at approximately $32.36 million.
Barra’s recent sell-off follows a 7.22 percent year-to-date increase in GM stock value so far.
Mary Barra’s transaction follows a significant sell-off from several other General Motors insiders over the past six months, including 51,471 shares sold by company Vice President and CAO Christopher Hatto, as well as 23,977 shares sold by company Executive Vice President Rory Harvey, resulting in an estimated $2.89 million and $1.27 million, respectively. Mary Barra alone has sold 994,863 shares during this period, generating an estimated total of $57.93 million. Notably, there have been no major insider purchases recorded during the same timeframe.
Insider purchases are a much better indicator than insider sales. There are many reasons to sell but really only one to buy.
DB2
I rec’d the entire thread. Murky stuff especially needs watchful watching.
We do know it.
The here and now is 20/20