Coinbase has joined five other major financial firms to support the Commodity Futures Trading Commission (CFTC) in a federal lawsuit challenging its authority over US stock perpetual futures. Following a judge's preliminary finding that the regulator likely exceeded its legal scope, Coinbase and its partners filed an intervention arguing that these contracts qualify as security futures under existing federal laws rather than swaps requiring SEC oversight. The companies, which include Kraken parent Payward, DRW Holdings, Jump Trading, and Paradigm Operations, maintain that their applications to list stock perpetual futures on Coinbase Derivatives, KalshiEX, and Bitnomial Exchange are valid. They assert that the absence of an expiration date does not automatically classify these products as security-based swaps, emphasizing that current rules allow for joint SEC and CFTC regulation of such instruments. Despite a US District Judge questioning the CFTC's authority and noting the contracts do not appear to satisfy the definition of a 'security future,' trading has not been halted. The court denied an immediate injunction request from the opposing Capital Markets Alliance, ruling that there was no likelihood of imminent irreparable harm while the case proceeds toward a preliminary injunction decision. This legal battle centers on whether stock perpetual futures should be regulated by the CFTC or the SEC. While the judge found the alliance likely to succeed in its challenge, the disputed approvals remain in effect pending further court rulings, creating regulatory uncertainty for Coinbase's derivatives platform and the broader market.