Ken Griffin Completes Takeover Of Brickell Block, Setting Stage For $2.5B Megaproject

It took four years and more than $770M for billionaire and hedge fund CEO Ken Griffin to reach the finish line in assembling a full-block site for his company’s future headquarters.

The task is finally complete after Miami commissioners last week approved the Citadel founder’s plan to buy the waterfront site of a 121-year-old, historically protected cottage, making way for one of the largest office developments the city has ever seen, part of a $2.5B project also set to include an apartment building and possibly a hotel.

Five Miami commissioners agreed last week to sell Jackson Cottage, the city's first doctor's office, in a no-bid sale for $3M to Griffin. The billionaire agreed to fund the national landmark's relocation to Coconut Grove, Dade Heritage Trust Executive Director Christine Chupp confirmed to Bisnow.

The deal would allow DHT, a preservation group that has occupied the cottage through a lease with the city since the late 1970s, to own both the cottage and the land it would sit on.

Commissioners were relatively tight-lipped on the deal during the vote, besides Commissioner Miguel Gabela calling Griffin "a good corporate citizen and a man of his word," the Miami Herald reported.

Griffin, the 37th-richest man in the world, started his buying spree by spending $360M in 2022 for the 4-acre vacant lot at 1201 Brickell Bay Drive and $286.5M for an office building across the street at 1221 Brickell Ave.

The billionaire purchased all of the condos — one by one, concealing his identity until last month — at the 22-story Solaris building at 1155 Brickell Bay Drive behind Jackson Cottage for roughly $125M, Bloomberg reported.

Demolition of the Solaris is expected to begin soon, according to a person with knowledge of Griffin's plans.

The waterfront site is set to house the future headquarters of Citadel and Citadel Securities, Griffin's market-making firm. In the original plans, the 1,032-foot-tall building included a rooftop, a 212-key hotel and only 1.3M SF of office space.

But after New York City Mayor Zohran Mamdani called Griffin out by name this spring in a viral video, pointing to his Manhattan condo to promote the city's new “pied-á-terre tax” on second homes worth more than $5M, Griffin said he would instead shift more Citadel employees to Miami.

The hotel component within the building was scrapped, though Citadel is still considering building one across the street. Citadel, which began soil-mixing on the site to prepare for vertical construction by the end of this year, expanded the project's office space to 1.7M SF, of which the company plans to take about 560K SF.

On his newly acquired property, Griffin also plans to build a 300-unit apartment building and a parking garage with more than 1,400 spaces.

With the massive project on the near-term horizon, Miami real estate players are anticipating a whole new wave of growth in office and employment following Miami's post-pandemic boom — which many credit Griffin for kicking off when he moved Citadel's headquarters to the city from Chicago.

When it moved into 830 Brickell to house its temporary headquarters, now home to 500 employees, it kicked off a wave of corporate migration, pushing office rents to record-breaking highs. The building is fully leased, with Peter Thiel's family office paying $250 per SF last month for 18K SF on its 44th floor.

Miami's average office rents have now surpassed New York’s, according to LoopNet.

Without those rent increases, office construction would be impossible, Colliers Senior Vice President Kevin Gonzalez said.

Many Miami professionals believe the lack of new office space is one of the main drivers in a recent slowdown in new-to-market activity — which went from making up to 21% of office activity in 2021 to 9% of activity in 2026, according to Blanca Commercial Real Estate's second-quarter report.

"These offices don't go up without the rents to support building a new office building," Gonzalez said.

"Now, you have the rents to actually support it, and you can point directly to Citadel's entrance into this market," he added.

In addition to Citadel's office, Banco Santander broke ground in April on a 50-story, 1.6M SF office tower to house its headquarters and offer space to other companies — the only substantial project under construction in the city.

Once the new space comes online, millions of square feet will be available to out-of-state companies looking to finally land new trophy space in a supply-constrained market where vacancy has dipped to 10.8%, according to Colliers' second-quarter report.

As of now, there are law firms and banks actively searching for space spanning more than 100K SF and tech companies looking to expand their presence, Gonzalez said.

And Griffin is investing part of his vast fortune to convince them to join him.

He teamed up with billionaire developer Stephen Ross to donate a combined $10M to Ambition Accelerated, a campaign created through The Florida Council of 100, to market the Sunshine State's business-friendly policies to out-of-state executives.

In the meantime, concerns over the city's affordability crisis are growing as the county's population shrinks and the cost of living outpaces New York City.

City officials and affordable housing developers have called on the incoming employers from large companies to help close the gap of the more than 90,000 units needed for residents earning about $75K a year, according to a 2025 report by Miami Homes For All.