Verizon Communications, a group led by Quicken Loans founder Dan Gilbert, and private equity company Vector Capital Management are among leading final round Yahoo bidders.

Citing a source familiar with the matter, Bloomberg reported that all three parties submitted bids by Yahoo’s Monday deadline, along with AT&T and another private equity firm TPG.

Yahoo is preparing to auction its search and advertising business. The company said its board made better progress on strategic alternatives.

The search engine giant is expected to select a winner this week.

Yahoo posted a sharp increase in its losses for the second quarter, led by a $482m write-down on the value of Tumblr.

Net revenues dropped by 20% from last year, with net losses increasing to $439.9m in the June quarter compared to $21.6m in the corresponding quarter of 2015.

Verizon plans to merge Yahoo with AOL, which it acquired for $4.4bn in 2015, to establish a digital advertising group.

The other bidder AT&T intends to compete with Verizon in advertising technology as it plans to expand in mobile video offerings.

Several reports have cited bids in a range of $4bn to $6bn for Yahoo's core internet assets, real estate and patents.

Bloomberg said Verizon’s bid was lower, in between $3.75bn to $4bn, excluding Yahoo’s patents and real estate.

Citing two people, the news agency reported that the company may raise its bid at the final deadline to clinch a sale.