South Street Securities Holdings

South Street Securities Holdings operates as a diversified financial services firm, providing technology-enabled solutions in securities financing, processing, execution, and analytics. The company was founded in March 2001 by a former management team from Citicorp/Citibank's primary dealer, repo, and structured finance divisions following the Citicorp-Travelers merger. The central figure in its founding is James E. Tabacchi, the current President and CEO, who secured the initial venture capital in 2000. Tabacchi's extensive 20-year career at Citibank, where he held various leadership roles including Treasurer of Citicorp Securities and co-head of the Primary Dealer desk, provided him with deep expertise in fixed income, structured finance, and risk management, which became foundational to South Street's business model.

The firm's core business revolves around providing repurchase agreement (repo) financing and reverse repo services for U.S. Treasury and agency mortgage-backed securities. It serves a diverse institutional client base, including banks, broker-dealers, hedge funds, asset managers, and mortgage lenders. Revenue is generated through the net interest spread on its matched-book repo portfolio, in addition to fees from its technology and service offerings. As a netting member of the Fixed Income Clearing Corporation (FICC), South Street mitigates counterparty risk and provides a steady source of liquidity for its clients. The company operates primarily through its broker-dealer subsidiary, South Street Securities LLC, which is registered with the SEC and FINRA.

South Street has expanded its offerings through strategic growth and acquisitions. Its subsidiary, Matrix Applications, provides technology and back-office services, including a collateral management system. The firm also has an asset management arm, South Street Capital Management, and provides equity financing and TBA (To-Be-Announced) mortgage hedging for mortgage originators. A significant milestone was the acquisition of GX2 Systems in early 2024, a software engineering company specializing in algorithmic trading and execution platforms for U.S. Treasuries. This acquisition enhances South Street's technological capabilities, offering clients advanced execution solutions through platforms like ExMode and strengthening its position in the institutional trading ecosystem.

Keywords: securities financing, repurchase agreements, repo financing, fixed income, broker-dealer, U.S. Treasuries, agency MBS, collateral management, algorithmic trading, securities lending, TBA mortgage hedging, financial technology, institutional finance, FICC, capital markets services, asset management, primary dealer, structured finance, institutional investors, hedge fund financing