What is the burden of documenting hours paid by a plaintiff in litigation?

"The fee applicant bears the burden of documenting the appropriate hours expended in the litigation and must submit evidence in support of those hours worked." Gates v. Deukmejian, 987 F.2d 1392, 1397 (9th Cir. 1992). The opposing party then has the burden of submitting evidence that challenges the accuracy or reasonableness of the hours charged or the facts asserted by the prevailing party in its affidavits. Id. at 1397-98.

"By and large, the court should defer to the winning lawyer's professional judgment as to how much time he was required to spend on the case; after all, he won, and might not have, had he been more of a slacker." Moreno v. City of Sacramento, 534 F.3d 1106, 1112 (9th Cir. 2008). However, courts may reduce the allowable hours if they are inadequately documented, duplicative, excessive, or otherwise unnecessary. See Chalmers v. City of Los Angeles, 796 F.2d 1205, 1210 (9th Cir. 1986), amended on other grounds, 808 F.2d 1373 (9th Cir. 1987).