Private company

Allied Universal

Allied Universal is an American private security and staffing company, based in Conshohocken, Pennsylvania and Irvine, California.1

Last updated Oct 18, 2026.

Overview

2016Founded1

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Allied Universal is an American private security and staffing company, based in Conshohocken, Pennsylvania and Irvine, California. Formed in 2016 by the merger of AlliedBarton and Universal Services of America, Allied Universal is the world's largest provider of private security guards. It is also the third largest United States–based employer globally with 800,000 employees.2

How it started

History

Allied Universal started as two different companies: AlliedBarton and Universal Protection Services.

AlliedBarton

AlliedBarton was founded as Allied Security in 1957 in Pittsburgh, Pennsylvania as a provider of contracted security guards and related services.

In 2004, Allied Security acquired Malden, Massachusetts-based Security Systems Inc. (SSI) and Atlanta, Georgia-based Barton Protective Services to form AlliedBarton Security Services - creating the largest American-owned contract security services company in the United States.

Universal Protection Service

From Wikipedia’s article on Allied Universal, shared under CC BY-SA 4.0.2

Timeline

  1. 2016Founded Founded1

Sources

The numbers on this page point here. Each one links to the record it came from.

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