UPDATE: Here's a link to the full interview in which Garber does seem to indicate that MLS is happy to have supporters own the trademark.
Almost two months after the dispute over who owns the rights to the Cascadia Cup trademark first went public, MLS Commissioner Don Garber appears to be ready to cede victory to supporters.
Don Garber has just confirmed to me that League would be happy with a resolution where fans own trademark to Cascadia Cup.— AFTN Canada (@aftncanada) March 1, 2013
This comes just a few days after Garber admitted during his annual State of the League address that MLS "didn't go about the process right."
Assuming this quote is accurate, the next logical step would be for MLS to drop their claim to the trademark. That would be a huge victory for the Cascadia Cup Council, a group created by ECS, Southsiders and Timbers Army. One imagines those groups would be willing to allow MLS to use the term "Cascadia Cup" in various marketing, but this would keep the league from selling sponsorship or directly monetizing the competition.
This is a similar setup to the Supporters' Shield, which is also owned by the supporters but used in various capacities by the league.