NEW YORK (CNN/Money) - Insiders at AOL Time Warner have sold $1.5 billion in America Online and AOL Time Warner stock since 1996, according to a published report Monday.

The Washington Post, quoting Thomson Financial's examination of insider sales records, reports that outgoing company Chairman Steve Case leads the list with $697.4 million in stock sales during the period. Robert Pittman, who resigned as chief operating officer of the combined company, is second on the list with $267 million in stock sales, while director James Barksdale, who received AOL stock for selling Netscape to AOL, sold $219.5 million, the paper reported.

Case last week announced his plans to step down as chairman of the company before the May shareholders meeting. The paper said he got many of the shares he sold free or at nominal cost. It said in 1994 he got more than a million stock options free, then later that year and in 1995 he got 2 million options for 2 cents each. It said millions of additional options came at prices between 9 and 55 cents apiece.

The paper did note that Case bought $24 million in AOL Time Warner stock in 2002.

The Post list did not include sales of the former Time Warner shares by executives of that company, which was bought by America Online in a deal that closed in 2001. The only Time Warner executive to make the list of top insider sales of either America Online or AOL Time Warner stock is CEO Richard Parsons, who was named last week to succeed Case as chairman. He has sold $35.3 million shares.

The Post said the sales by Case and some other top AOL executives could cause problems in shareholder suits that charge the company's improper accounting practices inflated revenue and stock price while its purchase of Time Warner was pending and immediately after the merger. Many of the stock sales also took place before the questionable accounting practices were revealed to investors, the paper said.

The questions about accounting for some advertising and commerce deals at America Online led the company to restate results for two years ended in the second quarter, erasing $190 million in revenue and $97 million in earnings before taxes and other items. The company still faces continuing probes by the Securities and Exchange Commission and the Justice Department in addition to the shareholder suits.