Last week, on September 13, thousands of HP printer owners were suddenly greeted by an error message when attempting to print, telling them that their ink cartridges were "damaged" and needed to be replaced. The reason has now been confirmed by HP itself: the company is locking out third party ink cartridges so that only its own will work going forward.

The change was apparently introduced as part of a firmware update back in March but it was timed to go into effect last week, though some of their printers prior to that already shipped with the timer. HP is calling it a move to "protect [its] innovations and intellectual property.”

Printers are often sold for little margin in order to earn profits over the life of it through the sale of consumables. This all about protecting one of the company's biggest profit centers, and while the move would have been unpopular one way or another, HP could have at least been forthcoming rather than sneaking in a 'self-destruct' timer and only disclosing it after the fact.

The HP OfficeJet, OfficeJet Pro and OfficeJet Pro X printers are affected. HP says these printers will continue to work with refilled or remanufactured cartridges with an original HP security chip.

Curiously, there are some reports from owners with original cartridges claiming they also got the error message, and that they weren't able to get the printer to respond in order to remove the supposedly damaged ink cartridge.