Hi, FYI see links below for details on HP's warranty policy....
Limited Warranty for HP Ink Cartridges, Printheads, and Related Supplies
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00206040
What this warranty does not cover
This warranty does not cover HP ink cartridges or customer-replaceable printheads that have been refilled, remanufactured, refurbished, misused, or tampered with. If failure or damage to ink cartridges or customer-replaceable printheads is attributable to the use of a non-HP, expired or refilled ink cartridge, or to the use with a non-designated HP or unauthorized OEM printing device, HP is not responsible for the cost of replacement or refund of the purchase price.
HP's limited warranty statements
For HP printer products, the use of a non-HP ink cartridge or a refilled ink cartridge does not affect either the warranty to the customer or any HP support contract with the customer. However, if printer failure or damage is attributable to the use of a non-HP or refilled ink cartridge, HP will charge its standard time and materials charges to service the printer for the particular failure or damage.