Who owns the Baseball Hall of Fame? Is it non-profit? Can they sell memorabilia Can players get tax deduction?

Answer 1

It is largely underwritten by the Clark Trust. The current chair of the Hall is Jane Forbes Clark, and that middle name should hint at how big the money behind the Hall is. (The Clark Trust owns a lot of land around Cooperstown and will not develop it, despite repeated and lucrative offers. They WANT Cooperstown to stay small-town quaint, and are willing to underwrite it.)

The Hall of Fame is a 403c not-for-profit educational institution.

It is a chartered museum within New York State, and I don't know the legalities well, but it is exceedingly difficult for a museum to sell items from its collection once those items have been acceded (taken in). It is easier to trade items between museums, but actually remove them and sell on the open market -- no.

If someone offers to donate a 3D item (basically anything not paper) to the Hall and they accept it, the donor is given a lifetime pass. That has value, and would have to offset any donation value for tax purposes. The Hall website has a FAQ about this. I don't think this is different for players than anyone else.