In 2015, he sold Guardsmark to Universal Protection Service, the largest private security company in the United States, and he served as its vice chairman until its 2016 merger with AlliedBarton.
[10] In 1971, Lipman disagreed with City College of New York Professor Lawrence Zeitlin's research, which showed companies would save money by letting good employees steal.
[11] Lipman believed most theft occurred as a result to addiction to narcotics, and the best way for companies to end this would be to hire undercover security agents, as employees would be more likely to confess to them than policemen.
[14][15] He added that passengers should be required to go through metal detectors, their carry-on luggage should be searched, and landing ramps should be equipped with closed-circuit television camera.
[16][17] Lipman expanded his business to home security in 1973, initially in Memphis, Houston, New Haven, Connecticut, and Concord, California.
[20][21] Lipman authored a book about security entitled How To Protect Yourself From Crime: Everything You Need To Know To Guard Yourself, Your Family, Your Home, Your Possessions, And Your Business in 1975.
[22][23] A 1981 report from the United States Department of Justice's Law Enforcement Assistance Administration quoted Lipman's advice that having a dog in the house was an efficient deterrent for burglaries.
[25] On September 11, 2001, Lipman instructed his employees to evacuate floors 48th to 52nd of the One Liberty Plaza, adjacent to the World Trade Center.
[7] Within a year, Lipman supported the Private Security Officer Employment Standards Act, a 2002 bill proposed by Senator Carl Levin of Michigan.
[7] Don Walker, the chairman and CEO of Pinkerton and chair of the American Society for Industrial Security, suggested Lipman had worked with Levin in "a cloud of secrecy".
[7] In 2004, Lipman's opinion pieces published in The New York Times as early as 1980 were discussed by the United States House Judiciary Subcommittee on Crime, Terrorism, Homeland Security and Investigations.
"[27] In 2015, Lipman sold Guardsmark to Universal Protection Service, making it the largest security company in the United States.
[30] He was a member of the Council on Foreign Relations,[10] where he was the namesake of the Chair in Emerging Technologies and National Security, currently held by Adam Segal.