Courtesy of mixedmartialarts.com:

Mike Fowler confirmed his invitation personally on the UG, stating: “They just sent me my ticket!” It hasn’t been disclosed at which weight he will be fighting. It is presumed to be  under 77 kg, but no official word yet from ADCC. Mike just beat Rodrigo Teixeira in the finals of the US Nationals. There have been unconfirmed rumors circulating that Fowler could possibly replace Bill Cooper, due to a possible knee injury.

Joel Tudor, who had an amazing run to win his category at the US Nationals, winning his first fight via sub, then subbing both Megaton Diaz and Rani Yahya in his next 2 fights to win the gold is also said to receive a last minute invite. Joel would probably be placed in the under 66 kg weight class.

No confirmation has been released by the ADCC.