Alibaba Group Holding Ltd. and Softbank Corp. are in talks with private equity firms about purchasing all of Yahoo! Inc., people with knowledge of the matter said, Bloomberg reported Thursday.

Alibaba and Softbank plan to work with investment firms that haven't signed the Yahoo nondisclosure agreement. The agreement bans companies that have signed it from talking with other firms about entering into strategic partnerships to acquire the online giant.

Yahoo has a stake of about 40 percent in Alibaba, and 35 percent of Yahoo! Japan, according to filings with the U.S. Securities and Exchange Commission.

Several other companies have reportedly shown interest in acquiring Yahoo!, including Microsoft Corp. and the U.S. private equity company Silver Lake Partners.

China's business press carried the story above on Thursday.