Lockheed Martin [NYSE: LMT] announced today that it will freeze its salaried defined benefit pension plan and transition employees to an enhanced defined contribution retirement plan. The change will take effect in a two-step approach, beginning on January 1, 2016 with the freeze of pay-based benefits and concluding with the freeze of service-based benefits on January 1, 2020. The company expects that the plan will be fully frozen effective January 1, 2020.