Efron v. Comr., T.C. Memo. 2012-338

(petitioner could not show existence of claimed NOL simply by filing return with statement setting forth amount of NOL deduction claimed and schedule setting forth NOL computation; court noted that NOL must be used in the two preceding years prior to carryforward year unless an election is made to waive carryback, and that petitioner didn't do either one; taxpayer failed to carry burden of proof of establishing existence of NOL).