The fate of multiple potential new office developments could hang on one potential anchor tenant.

Insurance giant Chubb is considering a new home for its Philadelphia office, the Philadelphia Business Journal reports. It currently owns and occupies the 361K SF office building at 436 Walnut St., and also leases about 140K SF at nearby One Washington Square from Keystone Property Group.

Chubb is considering a move into one of two proposed developments, where it would occupy about 400K SF. Parkway Corp. Senior Vice President Brian Berson claims to have a tenant in hand for the entirety of its 15-story, 400K SF tower at 20th and Arch streets, pending zoning approval, and the PBJ reports that Chubb would be that tenant.

Brandywine Realty Trust is reportedly also recruiting Chubb to be the anchor tenant at the first ground-up building within its Schuylkill Yards development district. The first portion of Schuylkill Yards, the public park Drexel Square, was completed this spring; the first building, a redevelopment of the Bulletin Building into lab and office space for Spark Therapeutics, is in progress.

Zurich-based Chubb is the largest publicly traded property and casualty insurance company in the world, and Philadelphia is home to the highest concentration of its employees of any U.S. city. Ace Insurance purchased 436 Walnut in 2004 for $22M, 12 years before it acquired Chubb and assumed its name. Staying in place remains an option, the PBJ reports.

If Chubb chooses 22nd and Arch, Parkway could possibly be kicking off two ground-up office developments in Center City 10 years into a recovery cycle that has only seen one (the Comcast Technology Center). Law firm Morgan Lewis has reportedly agreed to anchor Parkway's project at 22nd and Market streets. Parkway currently operates parking lots on both sites.