A felony domestic violence case against the 28-year-old was dismissed by the Santa Clara County District Attorney's Office earlier this month. The incident remains under NFL investigation, Garafolo reported.
Brock brings experience to Seattle. The veteran corner started 31 games the past two seasons in San Francisco, compiling 112 tackles, 25 passes defended and four interceptions. Pro Football Focus graded Brock as their No. 16 corner last season.
The Seahawks have been searching for a corner to play opposite Richard Sherman. Brock should slide into that role. DeShawn Shead continues to rehab from a knee injury. Rookie Shaquill Griffin has impressed during training camp, but could be leapfrogged by Brock. Nickel corner Jeremy Lane is currently dealing with what the team termed a "soft-tissue injury."