Alcoa Inc, the world's third largest producer of aluminum, has agreed to pay $384 million to settle charges by the U.S. Securities and Exchange Commission and the U.S. Department of Justicefor paying bribes to the kingdom of Bahrain through a London-based middleman. Alcoa World Alumina LLC will plead guilty before a federal judge in Pittsburgh on Thursday to violating the anti-bribery provisions of the Foreign Corrupt Practices Act.