Your right to buy and use alternative printer inks
is protected by the federal Magnuson-Moss Warranty Act. That does not mean that the manufacturer of your printer won't make it difficult for you to use alternative inks by developing elaborate cartridge chip technologies or building in functionality into their printers to detect non-original cartridges and displaying warnings in an attempt to keep you loyal to their brand. They may even threaten you if you choose other consumables by waiving their warranty at you. But the guiding word is that the use "may" void the warranty, rather than "will " void the warranty. The Magnuson-Moss Warranty Act (Public Law 93-637) is a U.S. Federal law that states that warrantors cannot require that only brand name parts be used with any product, as some printer manufacturers "imply".
THE MAGNUSON-MOSS WARRANTY ACT PROTECTS CONSUMERS AGAINST WARRANTY VOIDING
Legally, the Magnuson-Moss Warranty Act is a consumer protection law that states that: "No warrantor of a consumer product may condition the written or implied warranty of such product on the consumer's using, in connection with such product, any article or service (other than article or service provided without charge under the terms of the warranty) which is identified by brand, trade or corporate name” (15 U.S.C.A. 2302)
HOW THE ACT PROTECTS CONSUMERS' RIGHT TO PURCHASE ALTERNATIVES
The only exception to this rule is when the product would not function correctly without the product or service of the manufacturer, which is not the case with printer cartridges, or if a commission finds that it would be in the public's interest to include related products or services into the warranty, which is also not the case with printer cartridges. In fact, it is within the public's interest to provide a range of purchase options. Not only does this leave the consumer with much better value for money (where they can sometimes cost 50% less than the OEM cartridge), but it is a much better option for a wide range of reasons. The environment benefits from the fact that more cartridges are being reused instead of sent to landfill, as well as the fact that fewer cartridges need to be produced from scratch. These reasons reduce the carbon footprint of the consumer choosing such cartridges.
FURTHER READING ON THE MAGNUSON-MOSS WARRANTY ACT
If you are interested in learning more about the Magnuson-Moss Act, you can read more here
WHAT CAN YOU DO IF YOU DO NOT LIKE ARGUING WITH INDEPENDENT WIDE FORMAT TECHNICIANS ABOUT THEIR REFUSING TO TEST YOUR PRINTER WITHOUT OEM INKS?
Keep a spare set of functioning OEM cartridges around. The position of the technician is certainly within their rights. Many customers have reported that the technicians routinely fix their printers but make them buy a new set of color cartridges to verify the repair. Other customers say that they want to avoid the arguments by having the inks pre-installed when the technician arrives. Others have told us that some technicians are very familiar with STS inks and do final testing with them in place so the results are situational.