Plaintiffs lawyers in charge of more than 60 class actions over throttling iPhone batteries have asked a federal judge to order Apple Inc. to stop all communications with customers about refunds and replacements, unless they notify them about their right to sue.

Apple has been offering its customers $50 credit refunds or discounted battery replacements, since it admitted on Dec. 20 that it had installed software updates in older iPhones that slowed their battery life. Lawsuits claim Apple’s act was intentional, designed to force customers into buying new iPhones. Plaintiffs lawyers have insisted that Apple tell customers in both programs, many of whom are prospective class members, that they could still participate in the class actions. Last month, lawyers on both sides hit an impasse over the language of such a notice.