The Securities and Exchange Commission issued the filing Tuesday, though the actual filing was completed last week.
Turner acquired the shares following the Federal Communications Commission's January approval of the $124 billion merger between America Online and Time Warner, combining a top Internet service provider with one of the largest cable operators in the United States.
Under the deal, Time Warner shareholders received 1.5 shares in the combined company for each share they hold, while AOL shareholders received one share.
Turner sold his stock as part of a $1 billion promise to the United Nations.
Steve Case, AOL Time Warner's chairman, sold about $48.9 million in stock earlier this month. The 1 million shares, representing about 3 percent in the combined company, were sold for "financial planning purposes," a spokesman said at the time.
Shares of AOL Time Warner fell $3.41 to $44.95 in after-hours trading Tuesday on the New York Stock Exchange.