Thorn EMI was a British company that had ported some of their computer games to the TI99/4a just before TI withdrew from the market. Their modules were finished to test module status but Thorn did not release them.
Howard Greenberg of Arcade Hardware in Manchester, England, spent many hours over a lengthy period of time chasing the code, the personnel, and the rights before he was finally able in 1986 to release the three games on a disk.
Subsequently the games were ported to genuine modules in America.
The Thorn test modules were designed to plug into the right hand port of the console rather than the usual module port, and the integrated circuit was not in the usual black plastic casing but was on white ceramic, surface mounted.
Games for the TI99/4a
The games converted for the TI99/4a were Computer War (themed on the film War Games), River Rescue, and Submarine Commander.
The numerous changes of ownership and rights resulted in Thorn games being released under a number of labels for other computers also. River War was released by Thorn EMI, Creative Sparks, Sparklers and Alternative Software.
Thorn's roots were in radio and then television rental (as Radio Rentals and DER) with a subsequent expansion to manufacture of Ecko and Ferguson radio sets and Tricity cookers. By 1961 interests included Philco, Pilot and Ultra. At one time one third of British tv sets were owned by the company. The company further bought HMV and then EMI. The fragmentation led to a decline in the 1980's.
The computer side of Thorn (without the games software) ended its days as Data Sciences Ltd before it was bought by IBM in 1996.