Tangen likes to challenge his portfolio managers and demands that they record reasons for each investment decision made so it can be reviewed later on.

[4][5][6] In June 2010, Anjam Ahmad a trader who worked at AKO until September 2009 plead guilty to the charged of insider trading by the Financial Services Authority which involved 18 listed shares between 15 May 2009 and 22 August 2009.

During the trial it was revealed he passed information on what shares AKO would buy and sell on a particular day to Rupinder Sidhu, a management consultant and close friend that enabled him to spread bet and make around £524,000.

As it was the largest sovereign wealth fund in the world, his appointment immediately garnered attention and was extremely controversial given the circumstances.

Norway Lawmakers felt Tangen was not suitable for the job and he was coming in at a time the fund had been performing poorly due to the COVID-19 pandemic.

For example, it was revealed that there was an ongoing lawsuit between AKO and HM Revenue & Customs relating to incentive schemes as well as the fact that Tangen had personal investments worth $85 million in funds and companies based in tax havens.