Rams trade for Dante Fowler

Was listening to the NFL Network on Sirius this morning, and they had an interview with the Rams GM. He said they made this trade because they expect to have 1 or 2 compensatory 3rd round draft picks next season due to losing two free agents.

Didn't the Rams sign some free agents (Suh for starters) this season? I'm a bit confused how the compensatory process works, as they don't seem to be a candidate to receive anything, IMO, much less two extra 3rd rounders. Hoping someone can shed some light on this please...