U.S. antitrust regulators have given billionaire investor Carl Icahn the go-ahead to purchase large blocks of Yahoo stock, the Federal Trade Commission said on Friday.
The FTC, which routinely looks at large stock purchases, said the moves were approved in a listing that it puts out several times a week.
In mid-May, Icahn launched a campaign to replace Yahoo's board with new directors that would reopen buyout talks with Microsoft , saying the board had acted "irrationally" in refusing the software giant's bid.
Microsoft walked away from its sweetened $47.5 billion offer for the Internet company earlier this month. Microsoft had initiated an unsolicited bid originally worth around $44.6 billion at the end of January, which Yahoo rejected as insufficient.