Today in 1996, US Patent 5555992 A was issued, an invention of William A. Sedgeley, assigned to the Coors Brewing Company, for their “Double Hinged Opening for Container End Members.” Here’s the Abstract:

A container end member has a peripheral wall and integral central end wall portion with a stay-on-tab mounted on the central end wall portion for pivotal and rotational movement and a score line groove defined by two spaced apart terminal ends formed in the central end wall portion for defining a severable panel portion that is large enough so that when severed will provide an elongated opening that vents the container to permit pouring of the beverage in the container at faster pour rates than now available.