This is an interesting question ! Here is what I found in different spots on the net: Pinking means to decorate with a perforated pattern - cut in zigzag
Middle English pingen, pinken, to push, prick, from Old English pyngan, from Latin pungere;
Louise Austin of Whatcom, Washington, received United States patent number 489,406 on January 3, 1893 for "Pinking shears." The patent describes how "pinking scissors or shears" are superior to the existing tools at the time, "pinking irons" and "pinking cutters." The operation of the shears are described as "pinking" or "scalloping..
Benjamin Luscalzo, of Chicago, Illinois, received United States patent number 2600036 on June 10, 1952 for his improvements to "pinking shears".
Curiosity - searched here and there on the web