In a clash of cultural icons, the Beatles' record company, Apple Corps, wants Apple Computer to stop using its familiar logo, in the shape of an apple with a bite out of it, on the iTunes Music Store. Apple Corps contends that the use of the logo infringes on a 1991 agreement, which it says barred Apple Computer from using the logo in connection with the sale of music.


But it is the first case between the companies in the era of digital downloading. That technology, which did not exist in 1991, now accounts for more than 6 percent of music sales, the industry says.

"The agreement was intended to say, We do music, you do computer software delivery systems," Mr. Vos said of the 1991 deal. "The moment you cross the line is when you say you're in the record business."

The opening day of the trial was filled with light moments, as when Mr. Vos demonstrated the workings of iTunes for Justice Edward Mann, who took notes on a Dell laptop. Mr. Vos downloaded a copy of "Le Freak," a 1970's hit from Chic, and proceeded to play it for the court.

Without the logo, Mr. Vos said, "iTunes is a jolly good name."