The Sounders and the Seahawks have shared business operations since the former was established in 2007 but are now ready to go out on their own.
The soccer franchise and the football behemoth share CenturyLink Field as their home venue, and will continue to do so, but the Sounders will now operate independently according to majority owner Joe Roth.
"This is a sensible business decision for our franchise," the film executive said in a statement.
"Our vision is to grow our business to unprecedented levels both domestically and abroad. This move will position us to achieve that goal.
"The Seahawks have been vital to our early success and we thank Paul Allen and his organization for their support."
The relationship between the two clubs will not end, however, with Seahawks president Peter McLoughlin revealing there will still be joint projects for the two.
"This is a fantastic opportunity for [owners] Joe, Adrian [Hanauer] and Drew [Carey]," McLoughlin said.
"The Sounders will continue to be part of our family as we share CenturyLink Field and will work together on mutually beneficial projects."
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