Billions in the hole, battered hedge funder Ackman finally ditches his long, painful Valeant investment

Bill Ackman’s Valeant chapter is finally coming to a painful close.

The activist hedge fund manager has sold off his position in the embattled pharma, sources told CNBC on Monday, and while he’s not immediately vacating his spot on the company's board, he won’t seek re-election, either. His 27.2 million shares reportedly went for about $11 a pop—about $300 million all told—and Valeant’s stock headed south by as much as 9% on the news.

While it's unclear exactly when Ackman sold his stake, Bloomberg figures his losses on the shares he owned last year may have totaled $2.8 billion—with overall losses potentially coming in much, much higher.

But the way Ackman sees it, his Valeant holding wouldn't "move the needle" for his fund, Pershing Square Capital Management, even if the stock "doubled from here," he told the news service. Valeant shares closed Monday at $12.11, down from a record high of $263.81 in August 2015.

As Wells Fargo analyst David Maris figures, the move could mean more bad news for the company is on the way. "Some would argue that as an insider, Pershing Square has a better vantage point from which to judge the current challenges and prospects for Valeant," he wrote in a Monday note to clients. "... We believe investors would consider this as a sign that the next several years may not represent a major turnaround for the company."

After starting out as teammates at the M&A table with Valeant's then-CEO J. Michael Pearson, Ackman and the drugmaker have had a stormy couple of years. The relationship started to go downhill in November 2014, when the pair lost their hostile takeover target Allergan to white knight Actavis, and, as a show of faith, Ackman upped his Valeant stake—and then upped it again.

Those moves would only worsen the sting later, when Valeant ran into political pricing pushback, channel-stuffing allegations and a host of other problems. Eventually, things got so bad that Ackman put one of his own—Pershing Square Vice Chairman Steve Fraidin—onto the board, and then joined it himself after serious debt default concerns laid into shares once again.

But despite a whole lot of talk from Ackman and Valeant’s new execs, led by skipper Joseph Papa, the company hasn’t made much progress. While it’s managed to sell off a couple of assets to drum up much-needed cash, it’s also still plagued by turnover issues, suffering sales and myriad government investigations. Plus, Ackman's quiet-period appearance at an investor meeting last year hasn't helped Valeant overcome its shady reputation.

All told, Valeant was little more than "one very big mistake," as Ackman put it to CNBC last summer—and one that cost him and his investors dearly. 

For now, the two won’t be able to completely part ways, though. They’re still partnered up on at least one thing: a multimillion-dollar agreement to split the legal fees they incurred battling an insider-trading lawsuit from their days chasing an Allergan deal.

Editor's note: This story has been updated with analyst comments.