Inside Kalshi CEO Tarek Mansour's testy relationship with Indian casinos — and how it could pose an existential threat: ‘Lying little twerp'

Kalshi offers wagers across a slew of real-world events – from the Oscars to the weather in France to the prices at Costco – betting on sports events accounts for as much as 70% of an estimated $4 billion in revenue during the 12 months ended this July, according to a source close to the company.

While Kalshi says its wagers are financial instruments that it calls “event contracts” and “swaps,” the tribes have sued to stop them, countering that they amount to unauthorized sports gambling under federal Indian gaming laws.

Earlier this month, the Ninth Circuit of the US Court of Appeals ruled against Kalshi in one tribal suit, setting the stage for a showdown in the Supreme Court that risks crippling the app’s exploding business.

During the call, Mansour asked Rocha – an influential tribal leader who Kalshi hoped could help bridge a growing divide over their competing businesses – to join Kalshi as an advisor, insiders said.

But Rocha – an outspoken figure on social media who has branded himself Indian Country’s “attack dog” – swiftly rebuffed the offer.

In an interview with The Post, Rocha said Mansour’s overture came off like an attempt to reduce him to a token “cigar store Indian” so Kalshi could say “Hey, look, we have an Indian on our side.”

Rocha added that Mansour’s proposal looked like a ploy to “divide the tribal community” by creating the false illusion that Kalshi was an ally to Native Americans.

In reality, the New York-based startup was siphoning off revenue from Indian casinos and tribes were weighing how to address the threat, Rocha said.

A Kalshi spokeswoman said neither she nor Mansour recalled the initial call with Rocha.

While Rocha said the first call tainted his trust in the billionaire tech founder, insiders say a subsequent breakdown in talks has likewise left Kalshi execs fuming and fed up with the tribes’ “hypocritical” and sympathy-seeking arguments.

In particular, Kalshi is irked by the $46 billion in gambling revenue that the Indian Gaming Commission took in last year – a 5.3% bump from the prior year – while at the same time claiming it’s getting bled dry by prediction markets.

Kalshi execs have griped that tribal gaming is “a juggernaut, not an underdog” and they are running a “coordinated, not organic” campaign to stifle competition, even as they make noise about the loss of revenue to fund health and addiction clinics.

The previously unreported talks – which grew to include other top Kalshi executives and tribal gaming leaders – offer a behind-the-scenes look at how the gaming giants sized each other up shortly before the tribes slapped Kalshi with a trio of lawsuits intended to hamstring its business.