Today in 1974, US Patent 3812996 A was issued, an invention of Arthur Bunnell, assigned to Carling O’Keefe Ltd., for his “Bottle Carrying Case.” Here’s the Abstract:

Plastic carrying cases for bottles, especially beer bottles, are provided of a structure, in which, when the cases are stacked with bottles therein the tops of the bottles in one case engage the underside of the next upper case so that the load of the stack is supported through the bottles.