The Dolphins signed Ferrell on Monday.
In a corresponding transaction, Miami waived defensive lineman Kahlil Saunders. Ferrell was a steady fixture in San Francisco's front seven toward the end of last season, and he managed to tally 4.0 sacks in eight regular-season games with the 49ers. He'll likely have a harder time getting opportunities among a group of Dolphins pass rushers that figures to be significantly more productive than San Francisco's was in 2025.