We've already discussed the DSU Article 22.6 Gambling arbitration. Now it looks like we are headed for a GATS Article XXI arbitration:
Antigua has asked the World Trade Organisation (WTO) to arbitrate in a dispute over gambling with the United States, its lawyer in the case said on Thursday.
Mark Mendel told Reuters that Antigua, which last month won a related case against the United States for being shut out of the U.S. online gambling market, was continuing to seek discussions with Washington.
...
The European Union has said it reached an agreement with the U.S. over access to postal and courier, research and development and storage and warehouse services in compensation.
Washington has reached similar deals with Japan and Canada.
But no agreement has been reached with four other countries seeking compensation -- Antigua, Macau, Costa Rica and India.
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Mendel said Costa Rica had also filed for arbitration by the Jan. 28 deadline to do so.
Officials in the WTO missions of Costa Rica, Macao, India and the United States were not available for comment.
Watching the GATS Article XXI process unfold, for the first time ever, is going to very interesting. The Article XXI rules are here.
ADDED: Here is another article on the arbitration.