DUBAI, Oct 7 (Reuters) - Saudi Arabia's Kingdom Holding has paid $50 million to double its stake in microblogging site Twitter Inc , the Riyadh-based company said on Wednesday.

Kingdom Holding, the investment firm owned by billionaire Prince Alwaleed bin Talal, now owns 0.72 percent of Twitter, having originally invested $50 million in the tech company in 2011.

Twitter listed on the New York Stock Exchange in November 2013. Its market capitalisation is $18.7 billion, according to Reuters data.



(Reporting by Matt Smith; editing by Katie Paul) ((matt.smith1@thomsonreuters.com; 00971506354039; Reuters Messaging: matt.smith1.thomsonreuters.com@reuters.net))

Keywords: TWITTER KINGDOM HOLDING/INVESTMENT