Optiver is a proprietary trading firm and market maker for various financial instruments. The company was founded in 1986 in Amsterdam and has since expanded to have offices in Chicago, Sydney, and Shanghai. Optiver trades in a variety of financial products including options, futures, and equities. The company is known for its use of technology and quantitative analysis to make trading decisions. Optiver has been recognized as a top employer in the Netherlands and has won awards for its workplace culture.