Sims Custom Shop offers "Factory Ibanez Gotoh" tuners (scroll down to Tuners), and a couple of other places I've seen have mentioned "xxxx Gotoh" as if "Gotoh" is perhaps a patent or a characterisitc design manufactured by one or more "factories" that may or may not have the name Gotoh as part of their identity.

Perhaps (just guessing) there is no Gotoh factory, but Gotoh style tuners are made by several shops, and they're all called "Gotohs." (???????)

Sort of like every $3 fiddle Sears Roebuck ever sold said "Stradivarius" on the inside. ... (?)

John