Users who purchased a 27-inch iMac between December of 2012 and September of 2013 may experience hard drive or Fusion Drive failure "under certain conditions" due to problem with the hard drive component. Apple has now announced
a replacement program that largely covers the "late 2012" 27-inch iMac (though it may also include some early mid-2013 iMacs), and will contact registered owners of the affected units to offer a free swap out of the drives, regardless of warranty status.
The program will offer free replacements (and data transfer, if the drive is still operable) until December 19, or three years beyond the original data of sale, which ever provides longer coverage for the buyer, the company said in a statement. It has set up
a webpage for manual claims and to allow owners to check their iMac's serial number against the affected units, and said it will compensate owners who have paid to replace a failed 3TB HD or Fusion Drive from the affected models.
Apple has not commented on the specific brand of hard drive that is causing the issue, but a study by BackBlaze from February that
MacNN reported on noted that Seagate 3TB drives (in particular, separate from the rest of its product line) had an extraordinarily high rate of failure, approaching 44 percent for that capacity model only, a serious anomaly compared to the average problem rate for other drives from Seagate or other manufacturers.