Samsung has defended what it claims is its "lawful" decision to share disputed evidence with the press in a landmark case against Apple in the United States.

Samsung's lawyer said the evidence in question, which was blocked by a federal judge from consideration by the jury, had been requested by the media, and since it was already in the public domain, the decision to share it did not violate any court order.

Samsung argues that the evidence shows Apple copied elements of Sony products in designing the iPhone, so its claim that Samsung in turn ripped off the iPhone design does not hold water.

The case, which began on Tuesday, will pick up again on Friday, with the ruling expected at the end of this month.