Why Doug Kass shorted Apple by Philip Elmer-DeWitt @FortuneMagazine October 12, 2015, 8:16 AM EDT E-mail Tweet Facebook Linkedin Share icons Doug Kass, a small hedge fund manager with a large presence on CNBC, has shorted Apple. “The stock is moribund in my view,” he wrote Friday morning, citing the company’s past success and the “law of large numbers” (sic) as the stock’s greatest headwinds. “From a critical standpoint, Apple’s recent iPhone upgrade likely represents the last important smart-phone product-cycle for some time (size matters!). And it’s growing clear that Apple TV, Apple Pay and the Apple Watch won’t produce a meaningful incremental impact on AAPL’s sales and profits. Meanwhile Apple Mac sales growth is slowing rapidly.” I feel obliged to warn Apple investors that this is what Doug Kass does. He makes a bet in the market that Apple’s stock price will fall and then makes a big public show of it. On Twitter. On The Street. On cable TV. When the stock goes down and his bet pays off, he brags about it. When the stock eventually goes up, crickets. Past performance, of course, is no guarantee of future results, but so far Apple has always rebounded after a Kass event. It went up after Kass shorted Apple at $30 a share, at $130 a share, at $380 a share. Split adjusted, that’s $4, $19 and $54 a share. Apple closed Friday at $112.12. When Apple passed $700 (adjusted $100) in September 2012 and went into free-fall, Kass took credit in Barrons for the first $50 drop. I don’t know what he tweeted when the stock fell another $250. After I described his actions in 2013 as “self-serving,” he had me removed from his Twitter feed. In response to today’s post, Kass wrote on Twitter: “I view $AAPL as mature company that is overvalued.” I’ll repeat what I wrote in Oct. 2012—with credit to Jason (“the Apple slingshot“) Schwarz: Just when the average investor cracks, the hedge funds will load up their portfolios. If you’re an average investor, you would be well advised to ignore guys like Kass. See: Meet one of the guys tugging on the Apple slingshot Correction, October 12, 2015: An earlier version of this article mischaracterized Kass’s 2013 activity around Apple’s stock as a “pump and dump” scheme. It was not. Fortune regrets the error. Follow Philip Elmer-DeWitt on Twitter at @philiped. Read his Apple AAPL coverage at fortune.com/ped or subscribe via his RSS feed.