A Saudi Prince is suing Forbes magazine for libel, alleging his wealth was undervalued.
The publication says Prince Alwaleed Bin Talal has a net worth of US$20 billion, but says Forbes is short of the mark by US$9.6 billion.
Through his Kingdom Holding Company, Prince Alwaleed owns large stakes in Citigroup, News Corp and Apple Inc. He is also owner or part-owner of luxury hotels including the Plaza in New York and the Savoy in London.
He holds stakes in hotel management companies Four Seasons Hotels & Resorts, Movenpick Hotels & Resorts and Fairmont Raffles Holding, as well as hotel real estate such as the Hotel George V in Paris.
Forbes says the Prince and Kingdom Holding bought an estimated 3% stake in Twitter via the secondary market in 2012.
The Prince is ranked joint 26th on the list
His libel suit lodged in the UK High Court claims that the Forbes valuation process used "incorrect data" and "seemed designed to disadvantage Middle Eastern investors and institutions".
Two journalists are reportedly named in the defamation claim - the author of the article and another who was credited with additional reporting.
The prince is a grandson of Saudi Arabia's founder and nephew of King Abdullah. No date has been set for the hearing.
