0118 GMT [Dow Jones] RBS keeps Buy rating on BHP Billiton (BHP.AU), lowers price target slightly to A$47.63 from A$47.87 vs last down 2.2% at A$36.81. Says stock continues to offer compelling investment case as it's trading on a FY11 PER of 8x and 20% discount to RBS net present value estimate. "Global macro economic issues are currently acting as a headwind for a rerating, although a relaxation of the resource super profits tax, which is likely over the coming weeks (or days), could result in a positive market reaction," RBS says. Notes BHP shares ownership of some Gulf of Mexico assets with BP (BP.LN), which is divesting US$10 billion of assets to cover oil spill costs, and is likely to be at the negotiating table if they're up for sale. ([email protected]) Contact us in Singapore. 65 64154 140; [email protected] (END) Dow Jones Newswires June 30, 2010 21:18 ET (01:18 GMT)