0919 GMT [Dow Jones] Royal Bank of Scotland analysts downplay speculation that the Qatar Investment Authority [QIA] is preparing a bid of around 500p a share for Sainsbury (SBRY.LN). "Who knows (apart from the QIA and its advisers) is the real answer. This speculation seems to come every three to six months. It moves the share price up 5% and then over the next few days when no bid materialises, the shares come off again," analyst Justin Scarborough says. However, Scarborough says the business has developed since the QIA, a 26% shareholder in the grocer, walked away from a takeover in November 2007. Sainsbury declines to comment. QIA is not immediately available for comment. Shares +3.7% at 340p. ([email protected]) Contact us in London. +44-20-7842-9464 [email protected] (END) Dow Jones Newswires July 07, 2010 05:19 ET (09:19 GMT)