Hewlett-Packard last year filed patents for an ink cartridge-refilling machine, even though its disposable ink cartridge business ranks among its most lucrative. The U.S.-based firm has no refilling ...

Hewlett-Packard on Thursday accused a national cartridge reseller of refilling used printer cartridges with ink that relies on a formula for an HP-patented ink brand. In its letter to Cartridge World, ...