You’re right. There’s not a lot of information about King Lock Co. Many years ago (before the internet) I attempted some research. This is what I found:
It appears to have been founded in 1915 - or at least that’s when it first appeared in the city directory of Chicago. The address given was “rear 3233 N. Clark.” The following year the company moved to 319-325 W. Ohio. The company was listed in the 1917 directory, but not in 1923. (The 1918-1922 directories were missing.) Because King lock was listed as the assignor for two padlock patents of June 13, 1922, I presume the company went out of business some time after this date. There is also a little evidence suggesting that there might be some kind of connection between King Lock Co. and the Chicago Lock Co.
