Apple did not immediately respond to a request for comment.
Apple has previously acknowledged the problem, explaining the error as a security measure in a statement to the Guardian. The firm said that the error is triggered by processes that ensure iPhone's fingerprint scanner, called Touch ID, is working as it should and that no one has maliciously tampered with it. Without having Apple re-validate the sensor once a phone has been opened, the company said, it's impossible for the phone to tell whether the repair was above-board or not.
But Cochran and others are skeptical of the security argument.
Error 53 only rears its ugly head when downloading a newer version of Apple's operating system.
"If security was the primary concern, then why did the phones work just fine, sometimes for several months, without the software update," Cochran said in the release. "Error 53 only rears its ugly head when downloading a newer version of Apple's operating system."
Independent repairers have also noted that Apple could have simply disabled the fingerprint-scanning feature in cases where it senses unauthorized repairs, but allowed the home button -- and the phone -- to continue working. As Jessa Jones, the owner of iPad Rehab noted, iPhones can still be secure even when users skip Touch ID or use off-brand home buttons.
"The phone is still secured (if the consumer wishes) by the passcode lock just as all phones. If the phone is stolen, it cannot be reset and activated without the original owner's Apple ID and password--i.e. it is protected from theft with the iCloud activation lock," she wrote. "But it will work. Indefinitely. You can enjoy all the other functions of the phone. You can call, and text, take selfies, connect to WiFi and check email. You can play Candy Crush and FaceTime and surf the internet."