Bourse Blowup: Keystone, Adler Spar at Old City Conversions

A partnership behind the high-profile redevelopment of Philadelphia’s historic Bourse has unraveled into a courtroom fight, threatening to sideline a marquee Old City project at a critical juncture.

Keystone Development + Investment sued Dean Adler and several of his affiliated entities last month, accusing its joint venture partner of breaching agreements tied to the conversion of the 19th-century Bourse building and a nearby property at 400 Market Street, according to Bisnow.

Adler fired back with claims of mismanagement and funding shortfalls, setting up a two-sided dispute over who derailed the projects.

The venture, formed in June 2024, aimed to transform the Bourse into a 152-key hotel with a restaurant component while converting 400 Market into a 176-unit apartment building. But construction stalled last year as mechanic’s liens piled up, according to Keystone, and the relationship between the partners deteriorated.

Keystone alleges Adler failed to adequately capitalize the developments and improperly moved to replace it with PMC Property Group while exploring a pivot away from a hotel plan at the Bourse. Adler, in turn, claims Keystone sought an additional $10 million to keep the project afloat and warned of “catastrophic consequences” without fresh funding, while accusing the firm of gross mismanagement.

The dispute spilled into Delaware’s Court of Chancery, where Keystone secured a temporary restraining order in March that keeps it in control as managing member while litigation proceeds. The firm framed the ruling as validation of its stewardship, though the underlying projects remain in limbo.

Efforts to unwind the partnership have so far fallen short. Keystone chief executive officer Bill Glazer sought a roughly $9.4 million buyout tied to invested capital plus a 12 percent return, while Adler countered with an 8 percent premium.

The timing is especially fraught. The Bourse redevelopment had been slated for completion ahead of a surge in visitors expected this summer tied to the nation’s 250th anniversary celebrations, positioning the property as a key hospitality play overlooking Independence Mall.

— Holden Walter-Warner