Updated with additional information on Tree.com, Nordstrom, Eastman Kodak, and the latest pricing quotes.NEW YORK ( TheStreet) -- Shares of Yahoo ( YHOO) tanked in late trades on Thursday after the Internet search and content company made the stunning disclosure that it only learned at the end of March of the transfer in ownership of the Alipay third-party online payments business affiliated with Alibaba Group that occurred back in August 2010. Yahoo, which has a roughly 40% stake in Alibaba, first disclosed the change in a regulatory filing late Tuesday, and its stock fell 7% on massive volume of 131 million during Wednesday's regular session. The shares endured a relatively flat session on Thursday before issuing a statement on the news, saying it and Japan's Softbank, which reportedly owns a little more than 30% of Alibaba, learned on March 31 of "two transactions that occurred without the knowledge or approval of the Alibaba Group board of directors or shareholders," referrring to the transfer of ownership of Alipay to a company majority-owned by Alibaba CEO Jack Ma and then of the "deconsolidation of Alipay effective in the first quarter of 2011." Yahoo said its disclosure of the change on Wednesday reflected it "obtaining a better understanding of this complex situation" and said it continues "continues to work closely with Alibaba and Softbank to protect economic value for all interested parties." The stock was last quoted at $16.10, down 6.2%, on volume of 4 million, according to Nasdaq.com. The move marks a break below the shares' 200-day moving average of $16.71, and effectively erases the roughly 4.4% gain the stock had clocked in the past year. While the exact value of Yahoo's stake in Alibaba is a matter of intense debate on Wall Street, few would argue it's not being counted as a major multi-billion positive for the company. David Einhorn of Greenlight Capital disclosed a fresh investment in Yahoo earlier this month, and reportedly called Alibaba the company's "most valuable asset" in a letter to the hedge fund's shareholders, adding that he "wouldn't be surprised" if the stake was "ultimately worth as much as Yahoo's entire current market value." Yahoo's market capitalization is right around $22.7 billion, based on the recent share price. In Wednesday's SEC filing, Yahoo said the ownership shift was done to "expedite obtaining an essential regulatory license" and said the terms of the transaction were still being discussed.