Just sayin'. It's probably nothing.
https://archive.ph/KYdhu
German PDF
https://patentimages.storage.googleapis.com/67/24/a8/42bf94a3037ff9/CH651826A5.pdf
Don't know if they're still around and if there is more than one entity named Riker Laboratories but here's something.
https://opencorporates.com/companies/us_wv/24698
(post is archived)