The prediction market platform Kalshi becomes the exclusive partner of the US Open

According to Front Office Sports, the prediction market platform Kalshi has signed an exclusive agreement with the United States Tennis Association (USTA) to become the exclusive prediction market platform partner for the US Open. The agreement is effective immediately and was finalized only after the qualification rounds ended last week, with the report not disclosing financial terms. Kalshi has not yet been listed among the official partners of the US Open, and a blog post analyzing the women's singles events released earlier by the company included a statement saying that the company "is not affiliated with the US Open or WTA."

According to sources, as part of the agreement, the USTA is preventing other prediction market platforms from advertising at US Open venues and on television, including ESPN's broadcasts of the events, which is an unusual aspect of the agreement. Kalshi declined to comment, and representatives from USTA and ESPN did not respond immediately. The US Open is owned and operated by the USTA, and its CEO Craig Tiley took office on July 20 of this year, playing a significant role in facilitating this year's event agreement.

Both Kalshi and Polymarket are official partners of the NHL, and Kalshi has recently partnered with several MLB teams. According to data from The Block, since August, the total trading volume for Kalshi, Polymarket, and Polymarket US has reached $41.2 billion, with Kalshi accounting for $33.7 billion.