Defensive end Turk McBride has been tendered a contract by the Detroit Lions. His tender is reportedly at the second-round level (he was drafted in the second round back in 2007). If he were to sign elsewhere and Detroit declined to match the offer, the Lions would receive a second-round pick.
Because McBride has been in the league for four years, it's possible he could become an unrestricted free agent in the new CBA if the rules of free agency change. If he does, he would be free to sign anywhere without a team having to give up compensation for him. I'm sure the Lions will work hard to bring him back no matter what, though. He followed Gunther Cunningham from Kansas City to Detroit and has become a very solid player, recording a career-high five sacks in 15 games last season.
One player that may not be brought back is cornerback Brandon McDonald. He is in the same boat as McBride as far as being in the league for four years, but the Lions did not tender him an offer, meaning he is essentially an unrestricted free agent already.
McDonald joined the Lions via the waiver wire in late October and got more playing time as the season went on and injuries piled up. He broke his arm during the second game against the Packers, however, and was placed on injured reserve.