Katt

MEMORANDUM **

Claimant Ronald D. Katt filed a claim for Social Security disability benefits under Title II of the Social Security Act for the period between November 1, 1989, and January 22, 1997. The claim was denied by an administrative law judge (“ALJ”), whose denial became the final decision of the Commissioner of the Social Security Administration. Claimant sought review of that decision by the district court. The district court affirmed the denial of benefits. Claimant appeals. We review de novo. Gillett-Netting v. Barnhart, 371 F.3d 593, 595 (9th Cir.2004).

This case is governed by Armstrong v. Comm’r of Soc. Sec. Admin., 160 F.3d 587 (9th Cir.1998), which holds that an ALJ must call a medical expert if there is ambiguity in the record regarding the onset date of a claimant’s disability. “If the ‘medical evidence is not definite concerning the onset date and medical inferences need to be made, SSR 83-20 requires the administrative law judge to call upon the services of a medical advisor and to obtain all evidence which is available to make the determination.’ ” Id. at 590 (quoting DeLorme v. Sullivan, 924 F.2d 841, 848 (9th Cir.1991)). We held that the ALJ committed…