 At the beginning of 1893 Westinghouse engineer Benjamin Lamme had made great progress developing an efficient version of Tesla's induction motor and Westinghouse Electric started branding their complete polyphase AC system as the "Tesla Polyphase System", announcing Tesla's patents gave them patent priority over other AC systems and their intentions to sue patent infringers.In 1893, George Westinghouse won the bid to light the 1893 World's Columbian Exposition in Chicago with alternating current, slightly underbidding General Electric to get the contract.This World's Fair devoted a building to electrical exhibits.