Apple Computer opened its defence in London's High Court on Thursday against charges by the Beatles' company, Apple Corps Ltd., that it had violated a 1991 trademark agreement by moving into the music business, Reuters reported. Apple Computer lead counsel Anthony Grabiner argued that the market-leading iTunes music store was primarily a data transmission service, permitted by the agreement. "Data transmission is within our field of use," he said. Apple Corps, owned by Paul McCartney, Ringo Starr, John Lennon's widow Yoko Ono and the estate of George Harrison, has sued Apple Computer twice before. The 1991 out-of-court settlement, which included a $26 million payment by Apple Computer, set out areas in which each party would have exclusive use of their respective fruit-shaped logos. The interpretation of that agreement is now in dispute. Apple Corps is seeking a judgement of liability and an injunction against Apple Computer. If it succeeds, a subsequent trial will assess damages. --More 21 52 Local Time 18 52 GMT