=DJ GE Mortgage Insurer Unit Lets Triple-A Rating Go . By Christine Richard Of DOW JONES NEWSWIRES NEW YORK (Dow Jones)--GE Mortgage Insurance, a unit of General Electric Co. (GE), Friday said it plans to run its operations at capital levels consistent with a double-A rating and give up its triple-A ratings. That was followed promptly by action from the ratings agencies. Moody's Investors Service and Fitch Ratings downgraded their triple-A insurer financial strength ratings for GE Mortgage to double-A and assigned a stable outlook. "It simply makes sense for us to use our capital as efficiently as possible," Tom...