Gain Capital UK Limited has applied to cancel its authorization with the Financial Conduct Authority (FCA), a change the regulator's register dates to yesterday (Wednesday). The StoneX subsidiary has run the FOREX.com and City Index brands in Britain.The application closes out an entity the FCA has listed as authorized since December 2001, and which traded as City Index Limited until 2015.StoneX now runs its UK retail business through StoneX Financial Ltd, which retired the City Index brand on September 12 after retail FX and CFD revenue fell 19% in the June quarter.London's trading industry is coming home!A Plan Announced in JanuaryStoneX said in January that Gain Capital UK would give up its FCA license at a later date, and that FOREX.com's UK business would continue under StoneX Financial, which remains authorized by the regulator.The register shows Gain Capital UK can no longer hold or control client money. Its permissions still cover dealing as principal in CFDs, spread bets and rolling spot forex contracts, and the FCA notes that a firm in this position "must still meet our standards in dealing with its customers."The UAE License Still Carries the Gain NameThe January plan tied the timing to the Middle East. Gain Capital UK obtained a Category 5 license in the United Arab Emirates in August 2025 and planned to operate under it for several months before moving it to StoneX Financial, FinanceMagnates.com reported at the time.On Thursday, the register of the UAE's Capital Market Authority (CMA) still listed Gain Capital UK Limited as active and showed no StoneX entity. It is not clear whether a transfer is pending.Category 5 lets a firm promote services and introduce clients in the UAE, but not hold client funds or execute trades there. Vantage joined more than a dozen CFD brokers holding the introducer license in July.Three Decades of Name ChangesThe entity was registered as City Index Limited from 1995, according to the FCA register, and also used Barclays CFDs trading names between 2013 and 2018. GAIN Capital bought City Index in 2015, the year the company took its current name.StoneX acquired GAIN Capital for $236 million in 2020. A year later, Gain Capital UK cut its share capital by about 99%, as StoneX began winding down the Gain entity and merging it into its own operations.This article was written by Damian Chmiel at www.financemagnates.com.