General Motors Corp.'s pension plans will sell 100 million shares of DirecTV Group common stock, valued at roughly $1.5 billion, according to a news release from DirecTV. The transaction is expected to be completed by the end of the week. The sale cuts GM's DirecTV holdings by roughly 46% and will leave GM with 115 million shares of DirecTV common stock, less than 10% of the company's outstanding shares. As of Sept. 30, General Motors had $94 billion in defined benefit assets, according to Pensions & Investments data. Jerry Dubrowski, spokesman for Detroit-based GM, said that the transaction was initiated by US Trust, which serves as an independent trustee for GM employee benefit plans.