Just encountered a bunch of interesting signatures on ebay by seller tmdcards. By "interesting," I mean they appear to have a lot of authentic sigs from lesser-known players. Then I saw this Mantle. Anybody care to weigh in on its authenticity? It's authenticated by Global. I'm unfamiliar. Thanks!
https://www.ebay.com/itm/Mickey-Mantle-New-York-Yankees-Signed-Auto...