The Washington Post is making good on a promise it made in August when it agreed to sell its flagship newspaper to Amazon founder Jeff Bezos. Washington Post paywallThe $250M deal closed October 1. And today the Post unveiled the new name for the entity that owns six Post-Newsweek TV stations, Cable One cable systems, The Slate Group, Kaplan educational services and other properties: Starting tomorrow it will be called Graham Holdings Company, with its stock symbol changing from WPO to GHC. The newspaper was founded in 1877, and the Washington Post Co was incorporated in 1947 under Philip Graham.