Gulf Keystone Petroleum has won a three-year court battle over its disputed ownership of major oil fields in Kurdistan and said it plans to move from AIM to the main market. A London judge dismissed all of the claims made by Excalibur Ventures that it had a 30% rights over Gulf Keystone's Kurdistan projects in Iraq, principally its 12bn-barrel Shaikan field.Judge Christopher Clarke decided all issues in favour of GKP.Excalibur is a company owned by former US special forces soldier Rex Wempen, who claimed he had introduced Gulf Keystone's Chief Executive Officer Todd Kozel to opportunities in Iraq's Kurdistan region in 2005 and was owed his share of the spoils.After the hearing Kozel said: "We are very pleased to have achieved the best possible outcome from the point of view of the company and our shareholders." Kozel bemoaned the uncertainty and anxiety the company and its shareholders had endured over the last two and a half years but stressed the company could now move forward without this legal cloud looming. "The board and management will now focus on progressing the ramp-up in production and development of the Shaikan world class discovery in the Kurdistan Region of Iraq." On the corporate front, Kozel said the company's next objective was to move to the standard segment of the Official List by the end of 2013.The judge adjourned the hearing to a later date, which will be fixed in due course, for legal argument to be made on costs and any application for permission to appeal. Shares in GKP were up 15.7% to 217.25 at 15:48 on Tuesday.OH