Ken Griffin And Citadel

Citadel is a hedge fund and financial services group founded by Griffin in 1990. The company has grown substantially over time, and, according to HedgeTrace, it ranks as the second-largest hedge fund based on assets under management.

Griffin is widely regarded as part of the global financial elite. In addition to his role in building Citadel, he is a major philanthropist. He has served on the board of trustees of the Museum of Contemporary Art Chicago and has donated to institutions including the Art Institute of Chicago and the Museum of Modern Art in New York. His philanthropic contributions also extend to initiatives such as The Underline in Miami, COVID-19 relief and vaccine efforts, the U.S. Navy SEAL Foundation, and universities, including Harvard University and the University of Chicago.

Citadel was founded in Chicago, Illinois. However, its blueprint has evolved over time. The company quickly opened operations in New York City, maintains a significant presence in Europe in London and Dublin, and has a significant presence in Asia in financial hubs like Hong Kong and Singapore. In recent years, Citadel has expanded operations in Miami, Florida, including locating key players on its leadership team in this Southeast U.S. location.

Zohran Mamdani’s Rise To Mayor And His Battle With Ken Griffin

Zohran Mamdani rose to prominence in 2025, culminating in his election as New York City mayor. Central to his platform was a proposal to raise taxes on the city’s wealthiest residents and corporations, with revenue intended to fund expanded social programs such as universal childcare, free public transportation, and more affordable housing.

Despite this agenda, his first hundred days in office were marked by setbacks, as he struggled to secure support for tax increases at the state level. Meanwhile, Mamdani had proposed a budget for the city of over $127 billion annually, which would leave the city in a multi-billion-dollar deficit. Different from the U.S. Federal government, New York City is not permitted to run at a deficit, which puts immense pressure on Mamdani to identify new potential revenue sources to support his budget.

Without the ability to raise income taxes, Mamdani quickly turned to property taxes, where he initially proposed a 9.5% property tax increase on New York City residents. This proposal drew tremendous scrutiny as it would have effectively levied a tax on all residents, not just the wealthiest.

More recently, New York Governor Kathy Hochul has proposed a pied-à-terre tax. While the majority of the details for this tax have not been disclosed, the general gist is that property owners who do not actively use their property for living in or renting out would be assessed an incremental property tax. This tax would be restricted to properties that have a $5 million value or more, meaning that it would not be directed at the wealthiest property owners in the city.

In drumming up support for this tax, Mamdani shot a video outside of Griffin’s luxury New York City apartment, which is valued at $238 million. According to the New York Post, this video was seen as a “blunder” and an “ugly, unnecessary video stunt” designed to shame the New York City elites.

Following these developments, Citadel has reportedly reconsidered aspects of its New York City expansion plans, including a major office project estimated at approximately $6 billion. The project is expected to support roughly 6,000 construction jobs and over 15,000 permanent jobs.

Many of these roles are high-paying financial positions, including analysts with starting salaries often exceeding $200,000. In an interview with CNBC, Griffin reportedly stated that he will consider moving these jobs to the Miami, Florida, office.

Key Lessons For Mamdani As He Battles Ken Griffin On Taxes

Griffin’s statement underscores how public policy changes can have significant economic consequences. If all 15,000 jobs were relocated out of New York City, even conservative estimates suggest that lost income tax revenue could exceed expected gains from the proposed pied-à-terre tax. This does not account for additional losses in property and sales tax revenue.

What is potentially most alarming for Mamdani and his administration is that this planned exodus by Citadel and Griffin is transpiring with just proposed tax law changes. Thus, it is possible that the capital flight is a lower bound to an even larger tax collection decline for New York City.

While the outlook is dismal, there are many important considerations that the Mamdani administration must consider as it moves forward. First, directed backlash as individual billionaires cannot continue. Griffin did not threaten to pull his project from New York City when Mamdani was elected under proposed higher taxes, when a 9.5% property tax increase was threatened, or when the pied-à-terre tax was proposed. Instead, his threats weighed in when he was directly targeted and singled out in a social media stunt.

Second, Mamdani would benefit from providing more transparent and clear support for his vision and plans. New York City continues to operate under the guise of financial distress. While there is little doubt that the city needs substantial tax collections to operate, more can be done to articulate and sell the plans and usage of incremental tax funds to all taxpayers, particularly those who will be paying the majority of the increase.

Third, the tax collection estimates would benefit from clear modeling. For instance, the pied-à-terre tax estimates $500 million in incremental annual tax collections. However, the proposal includes no mathematical support or modeling. In fact, the proposal does not say much beyond the notion that there is a proposed tax, and this is who it will generally target. Many of Mamdani’s proposed tax increases have lacked this support, raising many questions about the overall welfare of the tax increase. Providing clearer estimates that are rooted in economics can be a beneficial step forward to illuminating the costs and benefits of proposed increases, especially as he faces contention from key billionaires, like Ken Griffin, on the efficacy of raising tax collections.