Polymarket and Kalshi have emerged as the biggest players in the burgeoning prediction markets industry.
The platforms have popularized betting on the outcomes of future events, from when the United States would invade Iran or Venezuela to whether Amazon cofounder Jeff Bezos would show up at this year’s Super Bowl.
The proliferation of the addictive trend, facilitated through major partnerships with the mainstream media, has caused an alarming number of young people to get roped into what essentially amounts to gambling.
Both companies have been hit by over a dozen federal lawsuits in the US, disputing whether they should be regulated as gambling operations like sports betting sites or federally regulated financial exchanges.
But there are some fundamental differences between Polymarket and Kalshi as well — and as NPR reports, that has their respective CEOs, Shayne Coplan and Tarek Mansour, locked in a bitter feud.
Kalshi has played it safe, at least relatively speaking, by becoming a Commodity Futures Trading Commission-regulated company that operates within the US. Polymarket has taken a far more Wild West approach and technically isn’t available to US-based consumers as it’s being run offshore — though that hasn’t stopped enormous numbers of US-based users from using the site through a VPN. Polymarket users can also make bets anonymously through cryptocurrency wallets, potentially allowing insider trading to flourish.
But whether most of the public has acknowledged this distinction remains unclear at best. Mansour, a 29-year-old MIT grad, has painted his company as a safer and ethically superior alternative to Polymarket. He has gone as far as to describe his falling out with Coplan as NFL quarterbacks Tom Brady and Eli Manning duking it out on the field during a podcast appearance earlier this year.
Mansour also admitted in late 2024 that he had coordinated an anti-Polymarket campaign on social media after Coplan’s apartment in New York City was raided by the FBI as part of a money-laundering investigation.
On the flip side, Coplan has been aggravated by the competition his company has been facing.
“Polymarket is Polymarket, and they’re a Polymarket copycat,” he seethed to CNBC last year, speaking of his rival.
“Kalshi hates getting lumped in with Polymarket,” consultant and prediction markets expert Dustin Gouker told NPR. “They’re trying to draw this line in the sand that they’re this CFTC-regulated prediction market and Polymarket is not.”
“I’m not sure that message is getting through, but it’s furthering the animosity between the two companies,” he added.
An enormous amount of money is at stake as the two prediction platforms vie for the number one spot. Users are pouring billions of dollars into both platforms, placing money on bets that range from innocent wagers, like the outcomes of baseball games, to far more ethically dubious bets about the US invasion of Iran.
Mansour has tread more carefully when addressing these more questionable bets than his counterpart at Polymarket. Case in point, users on Kalshi bet $54 million on when Iran’s Ayatollah Ali Khamenei would be “out as Supreme Leader” — but Mansour voided the bets as a “death carveout” after Khamenei was assassinated, outraging users. (On Friday, Kalshi was hit with a class action lawsuit accusing it of only invoking the carveout after the late Iranian leader’s death.)
Meanwhile, Polymarket has taken a vastly different approach by operating outside of the auspices of US regulators, which has attracted plenty of scrutiny.
Yet the Trump administration is showing little enthusiasm about reining the company in, dropping Biden-era investigations into Coplan’s company last year. The president’s son Donald Trump Jr.’s venture capital firm, 1789 Capital, has also poured millions of dollars into Polymarket, highlighting the company’s friendly relationship with the administration. (Incredibly, Trump Jr. is simultaneously a “strategic adviser” to Kalshi.)
Polymarket and Kalshi have been swept up in an arms race, trying to outdo each other with major partnerships. After launching a publicity stunt in the form of handing out free groceries to people in New York City, Polymarket reacted almost instantly — by opening what the company claimed to be the city’s “first free grocery store.”
More on prediction markets: Anonymous Polymarket Accounts Won $1.2 Million on Trump’s Iran Strikes in Suspicious Bets