St. Petersburg, Florida-based SecurityPoint's founder Joseph Ambrefe offered the TSA a license to his patent in 2005 in exchange for the exclusive right to advertise on the trays at U.S. airports.
The TSA had success testing SecurityPoint's technology and equipment, but refused SecurityPoint's offer.
The court said the TSA began using the same method with its own equipment later that year at most or all of the airports under its control, and SecurityPoint sued the U.S. government for patent infringement in 2011.
The government conceded that it had used the technology since 2008 in 10 airports including Dallas/Fort Worth, Boston Logan, Phoenix Sky Harbor and all three major Washington, D.C.-area airports.
The court rejected the government's arguments that SecurityPoint's patent was invalid in 2015, leaving questions about the extent of the government's infringement and how much it owed in damages.