Clarion Partners sells One Marina Park Dr. to Oxford Properties for $435 million - JLL Capital Markets handles sale

Boston, MA JLL’s Capital Markets group has completed the $435 million sale of One Marina Park Dr., a 494,938 s/f, Tier 1 office tower in the Seaport District. JLL represented the seller, Clarion Partners, in the sale of the asset to Oxford Properties. The sale represents one of 2026’s most impactful office transactions and underscores institutional capital’s appetite for well-located, Tier 1 assets as well as a return of institutional capital to the Boston office market. The transaction is also the largest pure-play office sale in Boston in the last five years.

One Marina Park Dr. delivered in 2010 as the anchor commercial asset of The Fallon Company’s $4 billion Fan Pier development. The 18-story tower is 99% leased to a high-credit tenant roster. With LEED Gold and WiredScore Platinum certifications, 375 below-grade parking spaces and floor-to-ceiling harbor views, the asset benefits from insurmountable barriers to entry in a submarket that has achieved 22% Tier 1 rent growth since 2019.

The property occupies one of the city’s last direct waterfront sites within Fan Pier in the Seaport, adjacent to Vertex Pharmaceuticals’ 1.1 million s/f global headquarters. Within a two-block radius of One Marina Park Dr. there are more than 35 dining options, 1,200 luxury housing units, 50 retail stores, hotels and museums. The property is also within walking distance of South Station, providing Red Line MBTA service and commuter rail service to the Greater Boston area, and the MBTA Commuter Ferry service at Rowes Wharf.

The Seaport continues to rank as a top-three nationally performing office micro-market, with 98% Tier 1 occupancy and Boston ranked as the second-hardest U.S. market to build, requiring a 48% rent gap to justify new speculative supply.

JLL’s Capital Markets Investment Sales and Advisory team representing the seller was led by executive managing directors Coleman Benedict and Riaz Cassum, managing directors Scott Carpenter and Patrick Shields, associate Chris Barry and analyst David Mega.

“This transaction validates what we’ve been seeing across premier office submarkets. Institutional capital is concentrating on irreplaceable trophy assets in supply-constrained, top-performing markets, underwriting to the data around outperformance and net effective rent growth,” said Carpenter. 

“One Marina Park Drive offered exactly what strategic buyers are pursuing in 2026: durable in-place cash flow with a track record of outperformance, meaningful embedded mark-to-market upside, and a waterfront position with no new construction in the pipeline. The competitive tension throughout the process reaffirms that best-in-class office fundamentals continue to command premium pricing.”