The "Mac App Store Update for OS X Snow Leopard" -- quite a mouthful, even for Apple's naming conventions -- was issued Wednesday so that 10.6 users could continue to access the Mac Apple Store, the apps available there, and most importantly, the upgrade to OS X 10.11, or El Capitan.
Included in the update was a renewed digital certificate required by the Mac app distribution warehouse. "The certificate ensures that you can continue to use the Mac App Store in Snow Leopard to purchase new apps and run any previously purchased apps that use receipt validation," Apple wrote in a short support document.
Most paid apps regularly check with Apple's servers to make sure that a receipt exists for the purchase before running, and use a signing certificate to validate that the app was, in fact, paid for.
It was unclear whether the certificate re-issue was related to the November screw-up when a new certificate prevented Mac users from running purchased apps, forcing some to delete the apps and re-download them from the store.
Apple did not immediately reply to questions about the Snow Leopard update, and whether it was connected to last year's snafu.
The Snow Leopard update was the first for the now-unsupported OS X 10.6 since September 2013.
Apple now patches the OS X editions designated as "n," "n-1" and "n-2," where "n" is the newest. Under that scheme, Snow Leopard was "n-3," and thus retired, when OS X 10.9, aka Mavericks, shipped in 2013.
Because OS X upgrades are delivered through the Mac App Store, Snow Leopard required access to the mart for users to migrate from the 2009 edition to a newer version, such as 10.11, or El Capitan.
There are still Macs running Snow Leopard: According to Web measurement vendor Net Applications, OS X 10.6 powered 4.8% of all Macs last month. Although that paled in comparison to El Capitan's user share (42.6% of all Macs) or even Mavericks (11.7%), it was larger than for successors like 2011's Lion (4%) and 2012's Mountain Lion (4%).
The 1-in-20 Mac owners who have hung on to Snow Leopard have proffered several reasons for sticking with the aged OS, including that it was the last version of OS X able to run applications designed for the PowerPC processor, the Apple/IBM/Motorola-crafted CPU used by Apple before it switched to Intel in 2006. Additionally, Snow Leopard was the final version able to run on Macs equipped with 32-bit Intel processors, making it impossible for owners of some older machines to move beyond 10.6.
The Mac App Store update for Snow Leopard can be retrieved by selecting "Software Update..." from the Apple menu.