The NFL has awarded 33 compensatory picks to 13 clubs. Seattle gets three, a 3rd rounder (97th overall), a 5th rounder (171), and a 6th rounder (215). This is the expected amount of picks that Seattle would receive, and the round numbers are exactly what was predicted by Over The Cap. The comp picks this year are not tradable, but that rule will change in 2017 and compensatory picks will be tradable.
With Seattle's three additional picks, they now have nine total, including four in the top 100 picks. That's a big deal.
Seattle made trades to acquire safety Kelcie McCray (using their 2016 5th rounder) and cornerback Mohammed Seisay (using their 2016 6th rounder).