Patent ID: 7452061

Claim:
A method of filling a printing-fluid container, comprising: providing a printing-fluid container that includes, while being filled, a substantially vertical leading surface having an outer-perimeter with a top edge and a bottom edge, wherein the printing-fluid container includes a printing-fluid interface positioned on the leading surface adjacent the bottom edge and an air-interface positioned on the leading surface proximate the top edge in generally vertical alignment with the printing-fluid interface, wherein the printing-fluid container includes a reservoir configured to hold a free-volume of printing fluid and air mixed together and wherein the printing-fluid interface and air-interface extend into the reservoir, wherein the printing-fluid container also includes an alignment pocket recessed from the leading surface, an electrical interface on the leading surface, the electrical interface being in electrical communication with a memory, and a keying pocket having at least one distinguishing characteristic used to indicate a type of printing fluid, the keying pocket being recessed from the leading surface; identifying the type of printing fluid indicated by the characteristic of the keying pocket; passing printing fluid of the type identified through the printing-fluid interface into the printing-fluid container; and permitting air to pass through the air-interface out of the printing-fluid container.