GTS (Global Trading Systems) is a New York headquartered proprietary trading and electronic market making firm, with additional offices including Chicago, London, Paris, Warsaw and Tel Aviv. Its core business is continuously quoting two sided prices across equities, ETFs, listed options, futures, fixed income and foreign exchange so other participants can trade against its book. Its lead broker dealer, GTS Securities, is a Designated Market Maker (DMM) on the floor of the New York Stock Exchange, a role in which it runs the opening and closing auctions and steps in to stabilize trading for the securities assigned to it. Within market making, GTS specialises in NYSE DMM services, ETF market making, wholesale (OTC) market making for retail order flow, and, since 2020, listed equity options market making, a broader combination than most purely electronic high frequency trading peers offer. As NYSE DMM it covers roughly 1,100 listed issues representing about 14 trillion dollars of market capitalization, close to a third of the exchange's listed float, which the firm has described as making it the NYSE's largest market maker. Its options unit, built substantially from the 2020 purchase of Barclays' equity options market making business, quotes more than 735,000 individual option series across roughly 2,000 underlying companies, with a specialist appointment in about 725 of them, on 13 global options exchanges. A separate unit, GTS Execution Services (GTEX), is an agency broker that pairs electronic execution with NYSE floor broker judgment for institutional clients. GTS was founded in 2006 by Ari Rubenstein, who remains chief executive, together with David Lieberman and Amit Livnat, colleagues from Pax Clearing Corporation who built the firm on the premise that electronic systems could trade faster and more consistently than floor based human market makers. Growth since then has come largely through acquisition: the NYSE DMM business of Barclays in 2016, Cantor Fitzgerald's ETF and wholesale market making units in 2018 and 2019, Barclays' equity options market making business in 2020, and HC Tech's foreign exchange trading unit in 2023. GTS Securities LLC and GTS Execution Services LLC are SEC registered broker dealers and FINRA members, and GTS Securities Europe Ltd is authorised by the UK Financial Conduct Authority. In January 2025 the SEC settled a 350,000 dollar enforcement action against GTS Securities for failing to file suspicious activity reports between May 2019 and July 2020 in its wholesale market making business, citing an AML surveillance program incapable of detecting suspicious trading. As NYSE DMM, GTS has taken on the listings of large, high profile companies at IPO, including Twitter and Pinterest, and counts Berkshire Hathaway and Alibaba Group among the issuers on its DMM roster; the firm says it has handled more than 250 NYSE IPO listings since 2013. CEO Ari Rubenstein testified before the US House Financial Services Subcommittee on Capital Markets in June 2024 on SEC market structure rulemaking, one indicator of the firm's active role in the ongoing US equity market structure policy debate.
