Since then, 33 states and U.S. territories have separately sued Apple on behalf of their consumers, while individual consumers in other states and territories filed a class action lawsuit.
The complainants are seeking up to $840 million in damages for e-book customers. The exact amount of damages was to be litigated at a trial scheduled for July 14.
The publishers—Hachette Book Group, HarperCollins Publishers, Penguin Group (USA), Macmillan and Simon & Schuster—previously agreed to pay more than $166 million to settle related antitrust charges.
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Last July, a federal court found Apple liable for colluding with the publishers after a separate non-jury trial in a case brought by the U.S. Department of Justice.
Judge Cote found that Apple took part in a price-fixing conspiracy to fight online retailer Amazon.com's dominance in the e-book market.
Apple is appealing that decision and Monday's settlement is contingent on the outcome of that appeal.