California Code
CHAPTER 1 - Of Ministerial Officers Generally
Section 262.5.

262.5. Service of a paper, other than process, upon the sheriff may be made by delivering it to him or to one of his deputies, or to a person in charge of the office during office hours, or, if no such person is there, by leaving it in a conspicuous place in the office.

(Added by Stats. 1951, Ch. 655.)