US66309967A and US3462767 flush valve patents. My father Harold F Larson & Robert L Schultz designed a few patents. They sold the rights I would like to know who?
I found four patents with Harold F Larson listed as an inventor. Two are for flush valves: US3341863A and US3462767A. US66309967A has too many digits to be a patent and doesn't show up in a search. Looking at the text of US3462767A I see: "N. Dak. 58421 Filed Aug. 24, 1967, Ser. No. 663,099" so I believe that is maybe an application number and US66309967A is just a typo in Google Patents.
I tried looking in the US Public Pair and the USPTO Global Dossier and found nothing at all. Based on comments by George White, my guess is the patents are just too old. You may be able to get the patents file wrappers from the the USPTO for a fee. My understanding is that licensing deals done post grant are not often registered with the USPTO so I don't think there is any way to figure out who the patents were licensed to beyond what you might be able to find through a Google search. Understand that the patents expired many years ago.