"The provisions tightening scrutiny of the antiquities market were contained within the sprawling National Defense Authorization Act, which Mr. Trump vetoed last week and which the House and Senate voted to override"

The New York Times:  Congress Poised to Apply Banking Regulations to Antiquities Market.

Nutshell summary: "Exactly how the new law works will be determined over the next year by the Financial Crimes Enforcement Network, a bureau within the Treasury Department, in consultation with the private sector, law enforcement and the public. Legal experts expect that the new antiquities regulations will be similar to others governing the precious metal and jewelry industries, where certain transactions are flagged to the authorities, who then determine whether they are suspicious. The law also seeks to end the use of shell companies to conceal the identities of buyers and sellers."

The usual good analysis from Nicholas O'Donnell here. (Nutshell summary: "Short version? It does less than it seems and probably isn't worth the cost, but it's a sign that change is coming and the market needs to get involved.")