I'm not sure about that. If the Phillies return him to the Red Sox he will go through waivers first. But if they do a trade I don't think he has to.
This does also raise the question: did the Phillies do a deal with LA for Victorino or did every other team pass on him?
Rule 5 Draft picks are assigned directly to the drafting club's 26-man roster and must be placed on outright waivers in order to be removed from the 26-man roster in the subsequent season. Should the player clear waivers, he must be offered back to his previous team for $50,000 and can be outrighted to the Minors only if his original club does not wish to reacquire him. A Rule 5 Draft pick can be placed on the Major League injured list, but he must be active for a minimum of 90 days to avoid being subject to the aforementioned roster restrictions in the next campaign.
Clubs may trade a player selected in the Rule 5 Draft, but the same restrictions apply to the player's new organization. However, a club may also work out a trade with the Rule 5 pick's original club to acquire his full rights, thereby allowing him to be optioned to the Minors under traditional circumstances.