A newly opened building that will serve as a diamond trading center in Surat, India, has dethroned the U.S. Pentagon to become the world’s largest office building. About the building: India’s Surat Diamond Bourse (SDB) is regarded as a “one-stop destination” for more than 65,000 professionals in the diamond industry, such as cutters, polishers and traders. While the building’s official website noted that it was ready to operate as far back as November 2022, its grand opening was reportedly postponed after only 400 members agreed to move into the building.