Ken Griffin says he had to watch it twice before it fully sank in.<\/p>\n
When New York City Mayor Zohran Mamdani posted a social media video on Tax Day filmed from outside Griffin\u2019s $238 million penthouse at 220 Central Park South \u2014 using the Citadel CEO as a prop to promote his new pied-\u00e0-terre tax \u2014 Griffin said his initial reaction was pure disbelief. \u201cThe first time, I couldn\u2019t believe what I was watching,\u201d he told CNBC\u2019s Sara Eisen on Tuesday at the Milken Global Conference. \u201cIt took a moment to digest what I was watching.\u201d<\/p>\n
What followed, Griffin said, was not just irritation \u2014 but genuine alarm.<\/p>\n
\u201cWhat really upset me about the video was the fact that it put me in harm\u2019s way,\u201d Griffin told Eisen. \u201cHe seems to have forgotten that the CEO of another American company was assassinated just blocks from where I live in New York.\u201d The reference was unmistakable: the December 2024 killing of UnitedHealthcare CEO Brian Thompson outside a Midtown hotel. \u201cTo put any citizen in harm\u2019s way is just inappropriate for one of our political leaders,\u201d Griffin said.<\/p>\n
\u201cTo turn me into a political puppet was just in poor taste, really poor taste.\u201d<\/p>\n
Mamdani\u2019s play<\/p>\n
Mamdani filmed the video on April 15, standing in front of Griffin\u2019s building and announcing what he called a first-of-its-kind pied-\u00e0-terre tax \u2014 an annual surcharge on residential properties valued over $5 million owned by non-full-time city residents. The proposal is projected to generate at least $500 million. Griffin\u2019s penthouse, which he purchased in 2019 for a record-setting price, became the centerpiece of Mamdani\u2019s pitch. The mayor declared, \u201cWhen I ran for mayor, I committed to taxing the wealthy. Today, we\u2019re taxing the rich.\u201d<\/p>\n
Griffin pushed back on the policy itself, too. \u201cThe tax, as a tax that discriminates against a narrow group of people, is also disconcerting,\u201d he said. \u201cAre they going to now have a special tax rate for those that own office buildings who live out of state? Like, where\u2019s this stop in New York?\u201d<\/p>\n
Miami wins<\/p>\n
The episode has had concrete business consequences. In response to Mamdani\u2019s move, Griffin said Citadel has already filed permits with the city of Miami to expand the square footage of its new headquarters by \u201cseveral hundred thousand square feet\u201d \u2014 a decision he said was made \u201cwith no regrets.\u201d Citadel will add far more jobs in Miami over the next decade as an immediate and direct consequence of the mayor\u2019s poor decision, Griffin told Eisen, saying it was in direct response to Mamdani\u2019s video. \u201cWe probably will go through with the building when it\u2019s all said and done, but I got to tell you, it\u2019s a real topic of debate.\u201d<\/p>\n Griffin declined to comment three times on his meeting with New York Gov. Kathy Hochul, which took place soon after the social media video. He said he was struck by a spokesperson for Hochul\u2019s office, who said that Mamdani had \u201cscored political points\u201d with the video. \u201cWow, like, that\u2019s real leadership, Governor Hochul,\u201d Griffin said sarcastically.<\/p>\n Griffin\u2019s Miami counterpunch didn\u2019t come from nowhere. Earlier this month, even before Tuesday\u2019s interview, Citadel had quietly scrapped hotel plans for its new Brickell headquarters and converted the project into a standalone 54-story, 1.7 million-square-foot all-office tower at 1201 Brickell Bay Drive<\/a> \u2014 a bayfront site Griffin purchased for $363 million in 2022.<\/p>\n The expansion is also the most visible real-world consequence yet of a deliberate, billionaire-backed campaign that Fortune has been tracking all year. In February, Fortune talked to Mike Simas<\/a>, president of the Florida Council of 100, who \u2014 alongside Griffin and Stephen Ross, the Related Companies chairman \u2014 seeded a $10 million national recruitment effort called \u201cAmbition Accelerated,\u201d targeting CEOs, founders, and investors weighing New York and California against Florida\u2019s Gold Coast. Last week, former Miami Mayor Francis Suarez<\/a> revealed in Fortune\u2018s pages<\/a> that he had joined the campaign as a senior advisor. Mamdani\u2019s penthouse video may have become the campaign\u2019s best recruiting advertisement.<\/p>\n Griffin closed with a broader warning for New York, invoking a familiar cautionary tale. \u201cDetroit was the most wealthy city in America per capita in the 1950s,\u201d he said. \u201cDetroit was the powerhouse of our country.\u201d The implication was sharp: no city, no matter how dominant, is immune to the consequences of driving away the people who fuel its economy. \u201cWith 1% of New York taxpayers paying 45% of all the taxes, the city is in a precarious position, if they make those who create value feel like they\u2019re best off moving their businesses and their lives to other jurisdictions.\u201d<\/p>\n Griffin\u2019s frustration with Albany fits a broader worldview that Fortune\u2018s Shawn Tully explored in March<\/a>: Griffin sees himself not just as a business builder but as a political force capable of reshaping the Republican Party and, by extension, American governance. Griffin will no doubt continue his long-running argument that no city, however dominant, is immune to the consequences of driving away its productive class.<\/p>\n