Looks like Groupon could be the ultimate IPO cautionary tale.

At least four of Groupon's earliest investors--including Marc Andreessen--have sold all or a substantial portion of their holdings in the company over the past several months, according to the Wall Street Journal.

The fire sale occurred amid a bevy of negative news about the company, including reports of low employee morale, salespeople leaving in droves for other start-ups, and poor leadership by company CEO Andrew Mason.

But perhaps the biggest factor in key investors dumping stock is the ever-falling share price. Groupon's stock market value has plummeted by more than 75% (or $10 billion) since the company went public in November.

Andreessen's venture capital firm Andreessen Horowitz invested $40 million in the company prior to the November IPO. The firm reportedly sold its 5.1 million Groupon shares after restrictions on selling the stock were lifted on June 1 and earned a $14 million profit.

Hedge fund Maverick Capital Ltd. reduced its number of Groupon shares from 6.33 million to two million at the end of March, according to SEC filings cited in the Journal report. Likewise, mutual-fund Fidelity Management & Research Co. sold approximately a third of its Groupon shares after April, and Sweden-based investment firm Kinnevik sold 8.38 million shares in June.

Some investors are buying in, however, including investment bank Morgan Stanley which recently bought 20 million additional shares and T. Rowe Price which tripled holdings in recent months.

Andreesen was one of several investors that cautioned Groupon about going public too early, the Journal reported. Other early Groupon investors that reportedly expressed similar concerns include John Doerr and Mary Meeker, partners at Silicon Valley-based venture capital firm and Gorupon backer Kleiner Perkins Caufield & Byers.