Rupert Murdoch ally Prince Alwaleed Bin Talal has sold his stake in 21st Century Fox – a major blow to Murdoch ahead of Fox’s annual meeting next week.

Prince Alwaleed has previously owned up to 6% of Fox and was one of the top owners of Fox’s Class B shares, which came with voting rights.

However, according to Bloomberg data shows that he sold his stake by the end of last financial quarter. This came after he reduced his stake to 4.98% in December 2015. Prince Alwaleed owned the shares through his investment firm Kingdom Holdings.

It’s not known who he sold his shares to or exactly when. Prince Alwaleed was arrested by Saudi authorites last week as part of an anti-corruption crackdown.

The move comes ahead of Fox’s annual meeting next week where Murdoch and his sons will face questions over the ownership structure of the company.

The Murdochs own around 39% of the voting rights but only 17% of the media company.

The news also comes after it emerged that 21st Century Fox had held merger talks with Disney.