Golub Capital BDC is a business development company (BDC) that provides debt financing to U.S. middle-market companies, defined as businesses with annual EBITDA below $100M. Nearly all of GBDC's loans are first lien, senior secured, floating rate instruments, with roughly 87% structured as "one stop" unitranche loans — a single instrument combining senior debt protections with junior capital economics. GBDC targets private equity-backed borrowers primarily for leveraged buyouts, acquisitions, and recapitalizations, with typical loan sizes of $10M–$85M per borrower. The portfolio totaled approximately $8.8B at fair value, spread across hundreds of companies, with a concentration in software, healthcare, and business services. GBDC is externally managed by GC Advisors, an affiliate of Golub Capital, which originates and underwrites all deals and has built relationships with over 420 middle-market private equity sponsors. GBDC earns income primarily through interest on its floating rate loan portfolio and origination fees. GBDC funds loans with a mix of equity and borrowed capital, targeting net debt-to-equity of roughly 1.1–1.25x. As a RIC-electing BDC, GBDC distributes at least 90% of investment income to shareholders, making it a high-dividend vehicle. GC Advisors earns a 1.0% base management fee on gross assets plus an incentive fee on income above an 8% hurdle rate.