The firms, however, also compete with pharmacies at grocery chains and discounters like Wal-Mart Stores Inc. Seth Bloom, an antitrust lawyer in Washington, said the new deal still raises antitrust questions that would require FTC scrutiny, including on the issue of Walgreens' growing national muscle. "Just because it's half the number of stores as the previous deal doesn't necessarily settle it," Mr. Bloom said. "It could make the review easier, but it's not a slam dunk yet." Tad Lipsky, acting head of the FTC's bureau of competition, said the FTC had "evaluated a number of divestiture proposals put forward by the parties" and would review any new transaction proposed. Walgreens said it expects $400 million in cost savings from the new deal within three to four years of closing. Walgreens will pay Rite Aid a $325 million termination fee for scuttling the larger deal. Shares of Rite Aid tumbled 26% on Thursday while shares of Walgreens added 1.7% to $78.37.