Does anyone else from here own 100% of the print run of official AU/GU cards of some certain player of any sport? That is, able to say that no-one else in the world has a single official AU/GU card of the given player?
Assuming the parallel means that there are other GU-versions of it too (say, red one that is /25, but has jersey or something) then that means there is at least 25 other Pau Gasol GU-cards made i.e. that's not 100%.
But it is a great card and most likely very valuable too, congratulations!
(Just in case "AU/GU" is not clear for someone: AU is a card that has a certified autograph i.e. a card or an attachment of that card guarantees by manufacturer, like Panini, that the autograph is authentic as opposed to an autograph some collector got from the athlete directly. GU is the same thing but with game used something, like jersey, glove, shoe, skate, stick or whatever. AU/GU simply means either of them - some card can easily of course be both as well)
I'd say that the unopened boxes doesn't really matter here. If you are able to know the finite amount of cards needed to accomplish this, then either you have them or then you don't. The unopened boxes can always (?) be told what they have inside. Not the exact cards that certain box has, but close enough to point a certain checklist and say "some of these cards". That is, I can't tell a single set that would have for example game-used cards that are _completely_ random, specifically to the extend that a collector can't have any kind of checklist of what there would possibly be.
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