The Electronic Frontier Foundation has called on HP to restore customer’s ability to use third-party ink cartridges in its Office Jet printers. It is also urging consumers to sign a petition, which as of this posts’s publication, has nearly 7,500 signatures.

In an open letter to HP Inc. President and CEO, Dion Weisler, activist Cory Doctorow calls on the company to take five steps immediately including apologizing to its customers and resorting the original functionality to its printers. HP seemingly knowingly activated the printer ink DRM under the guise of a security update, simultaneously removing features from its printers and violating the trust of its customers.

Last week HP pushed an update to its line of Office Jet printers. It was called a security update. However, upon installing, users quickly discovered that the printer would no longer work with third-party or recycled ink cartridges — only new HP cartridges worked.

Doctorow notes in his letter to HP’s CEO, removing an ability is a bait-and-switch tactic. HP had publicly announced a software update would be implemented that would restrict printer cartridge use. HP made this announcement in March, but the update was not pushed until September. HP knew for at least six months customers were buying a printer that would eventually no longer support a major feature — compatibility with third-party cartridges.

After releasing the update, HP issued a statement saying the purpose of this update was to protect the company’s innovations and intellectual property.

The entire letter is posted on EFF’s website and the petition is available here.