Allied Universal is an American provider of security systems and services; janitorial services; and staffing. The company was formed in 2016 by the merger of Santa Ana, California-based security and janitorial services company Universal Services of America, and Conshohocken, Pennsylvania-based security firm AlliedBarton Security Services. At the time of the merger, the combined company was reportedly the largest provider of security guards in the United States, with 140,000 trained officers between the two companies. In October 2021, Allied Universal completed a $5.1 billion takeover of British security firm G4S, creating a combined company of 800,000 employees, with revenues of more than $18 billion USD. The company maintains two corporate headquarters, one is in Santa Ana, California and the main headquarters is in Conshohocken, Pennsylvania.