Blockbuster, a subsidiary of Englewood, Colo.-based Dish Network Corp., plans to close about 300 U.S. stores, according to the Associated Press. Following the closures, which include locations that are underperforming or nearing the end of their leases, Blockbuster will operate about 500 stores. The store locations have not been announced. Dish Network bought the movie-rental retailer in March 2011. Last year, the company shuttered about 500 underperforming Blockbuster stores.