HP LaserJet 1015 Printer - Manual (Page 49)

ENWW Storing print cartridges 41
Storing print cartridges
Do not remove the print cartridge from its package until you are ready to use it. The shelf life of
a print cartridge in an unopened package is approximately 2.5 years. The shelf life of a print
cartridge in an opened package is approximately 6 months.
CAUTION To prevent damage to the print cartridge, minimize its exposure to direct light.