Adoboli, 32, from London, has pleaded not guilty to two counts of fraud and two counts of false accounting between 2008 and 2011.
Adoboli was arrested on 15 September 2011 when UBS uncovered what it termed “unauthorised trading” when working as a senior trader on UBS’s Delta One desk, which trades exchange traded funds.
He is accused of dishonestly using his position to try to make a personal gain, and causing UBS losses or exposing the bank to the risk of loss.
It is alleged he lost a total of $2.25bn.
The trial, taking place at Southwark crown court, is Britain’s biggest banking fraud.