"We're not going to sign something that says we did something that we didn't do, so we're going to fight," Cook said during an interview at the D11 conference on Tuesday.
He noted that Apple rejected a settlement because it was asked to sign a document that said it did something wrong. Cook said he didn't think Apple did anything wrong in that matter.
The Justice Department filed the antitrust lawsuit against Apple and five book publishers in April 2012. The government accused Apple and the publishers of conspiring to illegally fix e-book prices to boost profits and force e-book rival Amazon to abandon its discount pricing.
All five of the publishers involved -- Hachette Book Group, HarperCollins Publishers, Simon & Schuster (owned by CBS, which publishes CNET), Macmillan Publishers, and Penguin Group -- have now settled. The most recent publisher to fully settle was Penguin, which agreed to pay $75 million to bring an end to the long-running complaints brought by many states and private class plaintiffs.
In a pretrial hearing for the antitrust lawsuit last week, the judge presiding over the case said that she believed the Justice Department will be able to show direct evidence that Apple "facilitated a conspiracy to raise prices of e-books." But, she also said that no final decision would be made until after the trial.
With Apple being the only company left in the lawsuit, there has most likely been pressure for it settle too. However, as Cook made clear in the interview Tuesday, he maintains that Apple didn't take part in any wrongdoing and that no collusion with the book publishers took place.
If the case does go to court, Cook will have to testify. The trial is set to start on June 3.