A previously reported manufacturing defect is resulting in permanent data loss for numerous MacBook owners, according to Retrodata -- a UK-based drive recovery firm. The company says the critical flaw resides only in Seagate 2.5-inch SATA drives produced in China with a firmware version of 7.01, and an Apple spokesman has acknowledged that the company is looking into the matter. Retrodata says the problem is so severe that Seagate should recall the hard drives, and that Apple is responsible for replacing the drives free of charge.

"We've received a few reports that some MacBook consumer notebooks may have hard drive issues, and we're looking into it," Apple's Cameron Craig told InformationWeek.

The managing director of Retrodata, Duncan Clarke, says the company discovered that the head of the Seagate drives becomes detached from the read/write arms. The manufacturing defect ultimately results in "deep scratches" on the drive surface which often leads to permanent data loss.

Retrodata says it has received approximately 50 Seagate hard drives from MacBook owners hoping to recover their data since the summer of 2006, and that data was recovered in only three of those cases. Retrodata notes that the scratches that occur from the detached drive head often destroy the operating parameters that are unique to the hard drive which enable recovery firms to access "lost" data. However many MacBook owners immediately run MacBook utilities in an attempt to correct the problem, which results in more scratches.

"If you switch the computer off immediately, you might be able to recover the data," Clarke said. "I'm working on a fix, but it's going to take some time. I'm not optimistic."