The 25-year old arrives at CenturyLink Field along with the eighth overall selection in the 2014 SuperDraft and a 2015 conditional third round SuperDraft pick in exchange for defenders Patrick Ianni and Jhon Kennedy Hurtado and the 13th overall selection in the 2014 SuperDraft.
Sounders general manager Adrian Hanauer said: "One of the most difficult parts of this job is losing good people.
"Jhon and Patrick are both quality individuals who have been with our organization from the beginning. We wish them the best in Chicago."
Of Anibaba, Sounders head coach Sigi Schmid added: "Jalil is a center back who has tremendous upside.
"He has been very durable and we expect him to contribute right away."
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