Tradeweb Markets Inc. is an international financial services company that builds and operates electronic over-the-counter marketplaces for trading fixed income products, ETFs and derivatives. The company was co-founded in 1996 by Lee Olesky and Jim Toffey. Its customers include banks, asset managers, central banks, pension funds and insurance companies. It is known for having used technology to move the bond-trading market towards greater efficiency and transparency for institutions that trade fixed income and derivatives products. Tradeweb was launched in 1998, creating the first multi-dealer online trading network for U.S. Treasuries. In 2000, the firm opened its London office and launched marketplaces for trading European government bonds and agencies.