Atlanta's record per-square-foot price for office is about to be shattered yet again, this time by a San Francisco real estate investor.

Stockbridge Capital Partners has Three Alliance Center, the newest trophy office tower in Atlanta, under contract for more than $500/SF, CoStar reports, citing anonymous sources. Real Estate Alert reports that Stockbridge is set to pay about $525/SF for the 30-story, 506K SF tower, which would put the total purchase price at around $265M.

Tishman Speyer has scored a number of leases at what started as a speculative office tower in 2014, including big deals with Global Payments, Aon, State Street Corp., CBRE and, most recently, the first Atlanta location for the co-working operator Serendipity Labs.

The pricing, in part, reflects a rush of demand for Atlanta real estate by investors coinciding with a limited number of developments available for purchase. If Stockbridge Capital crosses the finish line at more than $500/SF, it would far eclipse the current record holder, set earlier this year with Transwestern's purchase of the State Farm office building in Central Perimeter for $457/SF.

Officials with Stockbridge Capital did not return calls seeking comment and officials with CBRE, which is marketing the tower for Tishman Speyer, declined to comment.

While not a household name, Stockbridge is no stranger to the Atlanta market. It owns Windward Oaks I and II office buildings in North Fulton as well as the Ashford apartment community in Brookhaven, according to CoStar.