We performed the tests using inkjet multifunction printers from four major manufacturers: Canon, Epson, Hewlett-Packard, and Kodak. Our results show that when these models reported their black ink cartridges as being empty, the quantity of unused ink ranged from about 8 percent in an Epson-brand cartridge to a whopping 45 percent in an aftermarket cartridge for a Canon printer. Our test
printers typically left more unused ink-in some cases significantly more-when