Webb has been added to the 40-man roster. The Dodgers had a spot open and no corresponding move was necessary.
Major League players generally have 72 hours to report after a trade, but nobody has said that Webb will be added to the 25-man active roster.
The Dodgers acquired Webb with Minor League catcher Brian Ward and a Draft pick for Minor Leaguers Ben Rowen and Chris O'Brien.
That came after Webb did not make the Orioles roster out of Spring Training, was designated for assignment and outrighted to Triple-A. Because he is owed $2.75 million, Webb cleared waivers once and probably would again.
Perhaps related to the uncertainty over Webb is the club's need for a fifth starter Tuesday night, with newly signed Scott Baker the favorite for a callup after throwing five solid innings Thursday at Triple-A.