Netsuke? How can such antiques currently be disallowed at auction?
Has your FIL considered Sotheby’s or Christies?
He might also do a little research on Japanese auction houses and go from there.
Really, what a mess - sorry your family is going through this.
The auction house simply told him that it was now illegal to sell ivory and returned the pieces to him. Sounds like they could have been confiscated if sold. I know he does have paperwork for most of the pieces (he used to own a small Asian/bonsai shop) but I guess they were either not old enough or the auction house didn’t understand the rules or didn’t want to deal with the hassle.
The pieces are absolutely beautiful, and I guess they’ll stay in the family for now ... or maybe they’ll be “lost” in a tragic boat accident.