Apple's trusted certificate — which is used by all third-party apps, Apple Wallet passes, and Safari push notifications and extensions — is set to expire in February 2016, and the manufacturer has issued a new certificate that will be valid until February 7, 2023.
To help protect customers and developers, we require that all third party apps, passes for Apple Wallet, Safari Extensions, Safari Push Notifications, and App Store purchase receipts are signed by a trusted certificate authority. The Apple Worldwide Developer Relations Certificate Authority issues the certificates you use to sign your software for Apple devices, allowing our systems to confirm that your software is delivered to users as intended and has not been modified.
The Apple Worldwide Developer Relations Certification Authority Intermediate Certificate expires on February 14, 2016, and we've issued a renewed intermediate certificate that, along with your website push certificate, must be included in all new Safari Push Notification push package signatures by this date. To make sure that new users are able to sign up to receive notifications, update and test your server with the renewed certificate.
Apple has also set up a support page that details how developers can incorporate and test the new certificate. Apple mentions that devs need not recompile or resubmit apps following the change, although any updates rolled out after February 2016 must include the new certificate. The upcoming change will not have any bearing on iOS users, but Mac users on El Capitan will need to switch to version 10.11.2. Snow Leopard customers will receive an update in January that will allow them to continue purchasing content through the Mac App Store:
Customers who have purchased and installed iOS apps, tvOS apps, or Safari Extensions will not be affected by the certificate renewal. Users running OS X El Capitan (v10.11 or v10.11.1) may receive a notification that your Mac app is damaged if it utilizes receipt validation to request a new receipt from Apple. They can resolve this issue by restarting their Mac or updating to OS X El Capitan (v10.11.2).
Mac App Store customers running OS X Snow Leopard (v10.6.8) will be unable to purchase new apps or run previously purchased apps that utilize receipt validation until they install the OS X Snow Leopard update which will be available via OS X Software Update this January.