Underdog is being sued by the company it bought its exchange and clearinghouse from following the announced acquisition by London-listed IG Group.
The lawsuit, brought by Aristotle International and Aristotle Exchange Holding Company, was filed in Delaware Chancery Court on Wednesday. The full suit was not available by publication.
Underdog launched its own exchange last month with the licenses acquired from Aristotle in March for an unspecified amount. IG Group swooped in with its offer for Underdog of up to $1.3 billion a few weeks after launching the in-house exchange.
“Apparently the Aristotle folks are unhappy with the money they’re making from the sale of their licenses, even though they will end up making more than anyone else in our sale to IG,” Levine said in an X post. “They’re trying to extract more.”
Aristotle did not immediately respond to LSR‘s request for comment.
Levine expresses confidence
On X, Levine divulged that Aristotle was negotiating for more money, and even tried to hold up the deal.
Aristotle thought it had leverage, he added.
“They didn’t and they still don’t,” Levine said. “They’re going to rack up a bunch of legal fees, create noise, but otherwise accomplish nothing. The deal will proceed and I have no doubt they will lose in court if they decide to take it that far.”
Who is named in the Underdog suit?
The full lawsuit brought by the two Aristotle entities were not immediately available at the time of publication.
According to the screenshot posted by Levine, there are 10 listed defendants, including Levine personally:
- Agon Holdings
- Agon Merger Sub I
- Agon Merger Sub II
- Aristotle Exchange DCM
- Aristotle Exchange DCO
- Aristotle Exchange Holding Company 2
- Brandon Stakenborg
- IG Group Holdings
- Jeremy Levine
- Underdog Sports Holdings
According to Levine, Aristotle is claiming “fraud”, “scheme”, “conspiracy”, etc.
Where the IG Group deal stands
The deal between IG Group and Underdog is pending regulatory approvals and is expected to close in late 2026 or early 2027.
IG Group has high expectations once the deal goes through.
“The third, announced on 30 July 2026, was the proposed acquisition of Underdog, which establishes IG as a leader in US prediction markets, more than doubling our US revenues and increasing US monthly active customers more than tenfold,” IG Group said in its first half earnings report. “It brings a scaled, founder-led franchise with a vertically integrated regulatory licence stack, a young, predominantly mobile-first customer base, and a product-first team whose pace of innovation can accelerate development across the Group.”
