U.S. telecommunications rivals Verizon Communications and AT&T are set to go through to the third and final round of bidding in the auction for Yahoo’s core Internet assets, according to people familiar with the matter.

After holding a board meeting to review second-round offers, Yahoo was to start reaching out to bidders as early as Monday to notify them whether they will make it to the next round, one of the people said.

Verizon, the biggest U.S. wireless carrier, is seeking to challenge AT&T, the second largest U.S. wireless provider, in the third round of bidding, even though its latest offer was at the low end of the $3.5 billion to $5 billion range of the second-round bids that came in last week, the people said.

Yahoo hopes to conclude the auction by next month, according to one of the people. The Sunnyvale, Calif.-based company started exploring a sale of the assets after coming under pressure from activist hedge fund Starboard Value.

A consortium led by Quicken Loans founder Dan Gilbert, and backed by Berkshire Hathaway Chairman Warren Buffett, also will make it through to the final round, the people added.

Some private equity firms that had made it through to the second round will not be invited to submit third-round bids,one of the people said.

The people familiar with the matter asked not to be identified because the bids were confidential.

Yahoo, Verizon and AT&T declined to comment. A Quicken Loans representative did not immediately respond to a request for comment on behalf of Gilbert’s consortium.

Not all offers involve exactly the same assets, with some bidders indicating they are not interested in some of the patents and real estate assets on offer, people have previously said.

Verizon is primarily interested in Yahoo’s advertising technology tools. Verizon has been examining how the other assets up for sale, such as search, mail and messenger services, could be combined with the corresponding businesses of AOL, which it acquired last year for $4.4 billion, Reuters reported last month.

AT&T has been seeking to catch up with Verizon in advertising technology as it seeks to expand in mobile video offerings.

A sale of Yahoo’s Internet assets would leave the company just owning a 35.5 percent stake in Yahoo Japan, as well as a 15 percent stake in Chinese e-commerce company Alibaba Group Holding, which accounts for most of Yahoo’s value.

In December, Yahoo scrapped plans to spin off its Alibaba stake, after investors fretted over whether that transaction could have been carried out on a tax-free basis.