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Responding to a July letter from Sen. Elizabeth Warren (D-Mass.) that large defense contractors acquiring their key suppliers is eliminating competition, a top U.S. regulator replied this month that putting firewalls in place so that acquired companies can continue to serve as suppliers to other contractors frequently doesn’t work. Warren’s letter was driven by concerns that the pending acquisition by Lockheed Martin [LMT] of Aerojet Rocketdyne [AJRD], one of two U.S. suppliers of solid rocket motors, would eliminate the last…
