Cal. Civ. Proc. Code § 2034.260

(a) All parties who have appeared in the action shall exchange information concerning expert witnesses in writing on or before the date of exchange specified in the demand. The exchange of information may occur at a meeting of the attorneys for the parties involved or by serving the information on the other party by any method specified in Section 1011 or 1013, on or before the date of exchange.
(b) The exchange of expert witness information shall include either of the following:
1. (1) A list setting forth the name and address of a person whose expert opinion that party expects to offer in evidence at the trial.
2. (2) A statement that the party does not presently intend to offer the testimony of an expert witness.
(c) If a witness on the list is an expert as described in subdivision (b) of Section 2034.210, the exchange shall also include or be accompanied by an expert witness declaration signed only by the attorney for the party designating the expert, or by that party if that party has no attorney. This declaration shall be under penalty of perjury and shall contain all of the following:
1. (1) A brief narrative statement of the qualifications of each expert.
2. (2) A brief narrative statement of the general substance of the testimony that the expert is expected to give.
3. (3) A representation that the expert has agreed to testify at the trial.
4. (4) A representation that the expert will be sufficiently familiar with the pending action to submit to a meaningful oral deposition concerning the specific testimony, including an opinion and its basis, that the expert is expected to give at trial.
5. (5) A statement of the expert’s hourly and daily fee for providing deposition testimony and for consulting with the retaining attorney.