Lexmark Return Programme cartridges are patented print cartridges sold at a discount in exchange for the customer's agreement to the licence requirement that the cartridges will be used only once and returned only to Lexmark for remanufacturing and/or recycling. The Return Programme cartridges are licensed for single use only and are designed to stop working after the delivery of a fixed amount of toner. A variable amount of toner will remain in the cartridge when replacement is required. In addition, the cartridge is designed to automatically update the memory in your printer to protect against the introduction of counterfeit and/or unauthorised third-party cartridges. If the customer does not accept these terms, replacement cartridges sold without these terms are available through www.lexmark.com.