Many Hewlett Packard and Lexmark consumers with inkjet printers may find that their ink cartridges are no longer working -- not because they are out of ink or because they're broken, but rather, because the manufacturers designed them to shut down after a certain amount of time. has received a few complaints from consumers who say their ink cartridges, although full of ink, just stopped working.

"I bought my HP ink 3 months ago, used it only twice and now my printer 'doesn't detect a cartridge!'" wrote Helga of Clearwater, Fla. "This is downright crooked. It should last for as long as there is ink in it."

The majority of ink cartridges with timers are manufactured by Hewlett Packard (HP) and Lexmark, said Alwin Morgenstern, chief operating officer of, a company that recycles ink cartridges.

A letter from "Beebo" to, a news website, reported that when he purchased discounted and expired HP ink cartridges, they wouldn't work. When he tried to use them, a warning would pop up saying the cartridges had expired.

Beebo examined the copper connector pins on his old cartridge and the new ones and found that the new ones had one extra pin. He removed that pin and sure enough, the cartridge printed fine.

For years, the cartridges have had suggested "sell by dates," said HP's senior ink and media scientist, Nils Miller. But in 1999, HP installed chips on some cartridges that communicate with the printer to tell it how long it has been since the cartridge was manufactured and installed in the printer. After a certain time, the printer will discontinue use of the cartridge.

Miller said it is a precautionary measure that prolongs the life of the printer's delicate ink plumbing.

"We are trying to maintain control over the interactions between the cartridge, ink delivery system and print head," Miller said.

HP and Lexmark installed this timing mechanism because many manufacturers began to move away from integrated ink cartridges, that is, cartridges that contain the ink, the delivery system and the print head all in one package. Instead, many printers now have all those parts built into the printer rather than the cartridge.

With an integrated ink cartridge, those delicate parts were replaced with each new cartridge.

Miller said that over time, ink can yield some sediment that could potentially clog the plumbing and the print head and that is why there is a timer.

Printers with built-in plumbing are nothing new, Miller said. But in the past, they were reserved for high end office machines that consumed larger quantities of ink in shorter periods of time. Many printer manufacturers began offering these same printers on the consumer level because the cartridges have more room to hold more ink. Miller said HP followed suit because of "market pressure."

The lifespan of many of HP's and Lexmark's expiring ink cartridges is 54 months after they are manufactured and 2.5 years after they are installed in the printer. A few of the cartridges have shorter lifespans of three years and 18 months after the cartridge is installed in the printer.

Morgenstern charged that the forced expiration date is a ploy for the manufacturers to make more money.

"Most cartridges will work fine at least one to two years after they expire," Morgenstern said.

Miller agreed saying that it's likely the cartridge would work fine after it expires.

"It doesn't mean those cartridges are filled with sludge immediately after the expiration date," Miller said.

But he said that HP has to be conservative because it could be very expensive for consumers to replace or repair parts in the printer.

Miller said consumers should strongly considered purchasing printers that utilize integrated ink cartridges.

"From an engineering and consumer point of view, integrated ink cartridges are good for customers who use their printers intermittently," Miller said. "If you're only going to use your printer once a week and then go maybe five weeks without using it, that's when you would want integrated ink."

Miller said non-integrated ink cartridges are good for consumers who use their printers regularly and will go through the ink faster than it can expire because those printers' cartridges frequently have a larger reservoir.

He also suggested consumers avoid stockpiling ink cartridges but rather just buy one or two at a time.

Consumers whose cartridges expire will receive no reimbursement, said Katie Neal, HP's spokeswoman. Her only suggestion was that consumers use the prepaid envelope that comes with the cartridge and mail it back to HP so it can properly be recycled.

If consumers would like to receive some reimbursement for their expired cartridge, they can send it to where they will receive as much as $3.60. For more information visit