Apple's main website for developers remains shut after hackers tried to steal sensitive information last week, forcing the iPhone maker to overhaul its database and server software to prevent future breaches.
Apple said on Sunday that no customer information had been compromised, but was unable to rule out the possibility that some developers' names, mailing addresses, and email addresses may have been accessed.
"Sensitive personal information was encrypted and cannot be accessed. However, we have not been able to rule out the possibility that some developers' names, mailing addresses, and/or email addresses may have been accessed," Apple told developers on its website.
The company also told developers that their membership, if set to expire, has been extended and all third-party apps will remain on Apple's app store for the duration.