Optiver Holding B.V. is a proprietary trading firm and market maker for various exchange-listed financial instruments.

Optiver trades listed derivatives, cash equities, exchange-traded funds, bonds, and foreign exchange.

[9] In November 2016, Optiver was reported to have joined a consortium to build a faster data transmission network between Chicago and Tokyo.

[12] In June 2019, Optiver joined its US-based rival, Virtu, in funding Equiduct, a competitor to national stock exchanges and trading venues.

[13] In April 2021, Optiver expanded further into the Asia-Pacific region with an office in Singapore, with a planned focus on commodity and equity products.

[23] For 11 days in March 2007, Optiver engaged in 19 instances of an illegal manipulation scheme known as "banging the close", with a minimum of 5 being noted as successful.