The opinion of the court was delivered by: Suzanne H. Segal United States Magistrate Judge
MEMORANDUM DECISION AND ORDER
Margaret Meehan ("Plaintiff") brings this action seeking to reverse the decision of the Commissioner of the Social Security Administration (the "Commissioner" or the "Agency") denying her application for Disability Insurance Benefits ("DIB") and Supplemental Security Income ("SSI") benefits. The parties consented, pursuant to 28 U.S.C. § 636(c), to the jurisdiction of the undersigned United States Magistrate Judge. For the reasons stated below, the decision of the Agency is REVERSED and REMANDED for further proceedings.
Asserting that she became disabled on June 1, 2007, Plaintiff filed an application for Title II DIB on October 3, 2008 and an application for Title XVI SSI on November 4, 2008. (Administrative Record ("AR") 139-144). The Agency denied Plaintiff's initial applications on March 3, 2009 and on reconsideration on August 6, 2009. (AR 69, 79). Plaintiff then requested a hearing, which was held before Administrative Law Judge Helen E. Heese (the "ALJ") on November 15, 2010. (AR 16). Plaintiff appeared with counsel and testified at the hearing. (AR 41). A vocational expert and a non-examining medical expert also testified at the hearing. (AR 58-60, 49-52). On December 3, 2010, the ALJ issued a decision denying benefits. (AR 13-24). Plaintiff sought review before the Appeals Council, (AR 11), which denied Plaintiff's request on July 25, 2011. (AR 1-3). On September 2, 2011, Plaintiff filed the instant action.
III. THE FIVE-STEP SEQUENTIAL EVALUATION PROCESS
To qualify for disability benefits, a claimant must demonstrate a medically determinable physical or mental impairment that not only prevents engagement in substantial gainful activity, defined by 20 C.F.R. § 416.910 as for-profit work involving significant and productive physical or mental duties, but that is expected to either last for a continuous period of at least twelve months or result in death. See Reddick v. Chater, 157 F.3d 715, 721 (9th Cir. 1998) (citing 42 U.S.C. § 423(d)(1)(A)); see also Tackett v. Apfel, 180 F.3d 1094, 1098 (9th Cir. 1999) (citing 42 U.S.C. § 423(d)(2)(A)) (noting that the impairment must render the claimant incapable of performing his previously performed work or "any other substantial gainful employment that exists in the national economy."). Unless those two requirements are met, a claimant is not disabled within the meaning of the Social Security Act. Tackett, 180 F.3d at 1098.
To decide if a claimant is entitled to benefits, an ALJ conducts a five-step inquiry. 20 C.F.R. § 416.920. The steps are:
(1) Is the claimant presently engaged in substantial gainful activity? If so, the claimant is found not disabled. If not, proceed to step two.
(2) Is the claimant's impairment severe? If not, the claimant is found not disabled. If so, proceed to step three.
(3) Does the claimant's impairment meet or equal the requirements of any impairment listed at 20 C.F.R. Part 404, Subpart P, Appendix 1? If so, the claimant is found disabled. If not, proceed to step four.
(4) Is the claimant capable of performing his past work? If so, the claimant is found not disabled. If not, proceed to step five.
(5) Is the claimant able to do any other work? If not, the claimant is found disabled. If so, the claimant is found not disabled.
Tackett, 180 F.3d at 1098-99; see also Bustamante v. Massanari, 262 F.3d 949, 953-54 (9th Cir. 2001); 20 C.F.R. § 416.920(b)-(g)(1).
The claimant has the burden of proof at steps one through four, and the Commissioner has the burden of proof at step five. Bustamante, 262 F.3d at 953-54. If, at step four, the claimant meets his burden of establishing an inability to perform the past work, the Commissioner must show that the claimant can perform some other work that exists in "significant numbers" in the national economy, taking into account the claimant's residual functional capacity ("RFC"), age, education and *fn1 work experience. Tackett, 180 F.3d at 1100; 20 C.F.R. § 416.920(g)(1). The Commissioner may do so by the testimony of a vocational expert or by reference to the Medical-Vocational Guidelines appearing in 20 C.F.R. Part 404, Subpart P, Appendix 2 (commonly known as "the Grids"). Osenbrock v. Apfel, 240 F.3d 1157, 1162 (9th Cir. 2001). When a ...