Shares of European payment processor Adyen BV doubled on their trading debut on the Euronext Amsterdam exchange on Wednesday. The shares, priced at 240 euros ($282) each, opened at €400. The stock hit an intraday high of €503.90 and was trading at €433.30 at last check. Adyen was named earlier in 2018 as "primary partner" for EBay Inc. payments, a move that relegates its fellow payments processor PayPal to a lesser role on the auction site. Its other high-profile partners include Uber Technologies Inc and Netflix Inc. Adyen is the largest technology IPO in Europe this year, and one of the largest tech companies to go public in the Amsterdam exchange, The Wall Street Journal reported.