US media reports have fanned speculation that Microsoft is still working on a bid to acquire Yahoo to bolster its position against search rival Google.
An investment group led by US technology sector executives is putting together a Yahoo takeover deal to be financed mainly by Microsoft, said the Tech Crunch website.
Citing unnamed sources, Tech Crunch said the investors are looking to borrow $20bn from Microsoft to buy Yahoo for about $15 a share.
The deal would give Microsoft a way to control Yahoo's search assets without having to own the rest of the company, Tech Crunch said.
Bloomberg financial news service later dismissed the possibility of such a deal, citing unnamed sources as saying Microsoft was not discussing any financing plan for a Yahoo deal.
Neither Microsoft nor Yahoo has commented, but Yahoo issued the standard response that it would not comment on rumour or speculation, Bloomberg said.
Microsoft chief executive Steve Ballmer dismissed the possibility of another buyout offer in November, but said Yahoo's search business was still of interest.
In December, Yahoo shareholder Ivory Investment Management called on the board to re-open talks with Microsoft to buy Yahoo's search business.
Ivory made the call in an open letter to the Yahoo board as 1,500 Yahoo employees received redundancy notices as part of the company's cost savings plan.
Yahoo has suffered a $30m loss in value since outgoing chief executive Yang rejected a buyout offer from Microsoft at $33 a share or $47.5bn in February 2008.