HP Inc. today said it will restore the ability of certain OfficeJet printers to use third-party ink cartridges, after being criticized for issuing a firmware update that rejects non-HP ink.

But HP is still defending its practice of preventing the use of non-HP ink and is making no promises about refraining from future software updates that force customers to use only official ink cartridges.

HP made its announcement in a blog post titled "Dedicated to the best printing experience."

"We updated a cartridge authentication procedure in select models of HP office inkjet printers to ensure the best consumer experience and protect them from counterfeit and third-party ink cartridges that do not contain an original HP security chip and that infringe on our IP," the company said.

The recent firmware update for HP OfficeJet, OfficeJet Pro, and OfficeJet Pro X printers "included a dynamic security feature that prevented some untested third-party cartridges that use cloned security chips from working, even if they had previously functioned," HP said.

For customers who don't wish to be protected from the ability to buy less expensive ink cartridges, HP said it "will issue an optional firmware update that will remove the dynamic security feature. We expect the update to be ready within two weeks and will provide details here."

This customer-friendly move may just be a one-time thing. HP said it will continue to use security features that "protect our IP including authentication methods that may prevent some third-party supplies from working."

We spoke with an HP spokesperson who confirmed that HP reserves the right to issue future updates that prevent non-HP ink cartridges from working.

Without the optional firmware update, printers will only be able to use third-party ink cartridges that have an "original HP security chip," the company said. We asked HP for examples of third-party cartridges with the original HP chips. While HP did not provide any specific examples, a spokesperson said that "A cloned product with an original HP security chip will work," and that "HP’s dynamic security recognizes refilled and remanufactured supplies that contain the original HP security chip."

HP did apologize for its poor communication about the firmware update and promised to be more "transparent" in the future. But that alone won't satisfy the Electronic Frontier Foundation, which called on HP for a public commitment to never again use its software update process "to distribute anti-features that work against [HP] customers' interests."

The EFF told Ars today that it's glad to hear about the firmware update, but it wants to know what HP's plans are for informing users. "Today, the vast majority of people who use the affected printers do not know why their printers lost functionality, nor do they know that it’s possible to restore it," EFF Activist Elliot Harmon said. "All of those customers should be able to use their printers free of artificial restrictions, not just the relatively few who have been closely following this story."