MEMORANDUM**

California state prisoner Frederick Douglas Stills appeals pro se the district court’s judgment dismissing his third amended complaint in his 42 U.S.C. § 1983 action. We have jurisdiction under 28 U.S.C. § 1291. We review de novo, Resnick v. Hayes, 213 F.3d 443, 447 (9th Cir. 2000), and we affirm.

The district court properly dismissed Stills’ claim for medical mistreatment because his third amended complaint failed to state a claim upon which relief could be granted. See Estelle v. Gamble, 429 U.S. 97,106, 97 S.Ct. 285, 50 L.Ed.2d 251 (1976) (concluding negligent medical treatment does not state a valid claim under the Eighth Amendment).

Contrary to Still’s contention, an amended complaint supersedes a prior complaint. See Forsyth v. Humana, Inc., 114 F.3d 1467,1474 (9th Cir. 1997).

Stills’ remaining claims lack merit.

AFFIRMED.