When Allied Barton merged with Universal Services of America a couple years ago, I stated that the combined company would be expected to generate revenue of $4.5 billion, making it the largest in North America and third largest in the world.

https://www.securitymagazine.com/blogs/14-security-blog/post/89261-what-will-the-latest-mega-merger-mean-for-the-present-and-future-of-guarding-companies