Saudi Aramco shares are spiking after hitting the market in the world's biggest-ever IPO

Shares in Aramco, the Saudi-owned oil giant, spiked 10% Wednesday when they hit the market in the world's biggest-ever IPO.

The spike came as shares began trading on Riyadh's Tadawul stock exchange, after years of wrangling over where they would list.

Due to regulations on the Tadawul, a 10% spike was the maximum possible for the debut.

The offering raised $25.6 billion, according to the Financial Times, putting it just ahead of the previous record IPO, which was the $25 billion amassed by Alibaba in 2014 in the New York Stock Exchange.

This is a developing story, more to follow.