The JSA cert checks out as being for a Baugh signed jersey. I doubt the jersey is a legit M&N if that matters at all to you (and, of course, the seller does not advertise it as such). I'm sure you know this, but you can check those JSA numbers (D77111) at
James Spence Authentication (though I'm not sure how much stock you put in the JSA certs, they seem good to me but I never like it when a cert doesn't give the date and location of a signing). I'm also sure you know this, but PSA/DNA offers a cool service for eBay where they will offer an opinion on whether their expert thinks an auto is legit
PSADNA QuickOpinion(SM).
To answer the question of why Rich was concerned about the signing date, it is because he is an informed guy who knows that the last signing Baugh did was in 2004.
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