While the Seattle Sounders and Vancouver Whitecaps will face off in an MLS is Back Tournament group stage match that will count toward the regular season, their match won't count toward the 2020 Cascadia Cup standings, according to a statement from the Cascadia Cup Council.
Any additional matches between the Sounders, Whitecaps and Portland Timbers during the tournament's knockout phase also would not count, according to the statement:
On June 10, 2020, representatives of the Cascadia Cup Council unanimously agreed that "MLS is Back" tournament matches played behind closed doors, along with any future matches played in MLS stadiums where supporters are not present, will not count towards Cascadia Cup Standings in 2020. In order to continue the Cascadia Cup’s tradition of competitive balance, each club must complete both home and away matches against each of the other clubs, and 2020 will operate as with any other season the Cascadia Cup was awarded while Portland, Seattle, and Vancouver played in MLS together. As always, the Cascadia Cup Council and the supporter groups it represents stand with the MLSPA.
The Cascadia Cup was originally founded in 2004 by supporters of the three clubs when they were rivals first in the A-League and then in USL-1. The trophy has been contested between the three teams at the MLS level since 2011, with the Sounders currently the reigning champions.