Cal. EVID § 1062

(a) Notwithstanding any other provision of law, in a criminal case, the court, upon motion of the owner of a trade secret, or upon motion by the People with the consent of the owner, may exclude the public from any portion of a criminal proceeding where the proponent of closure has demonstrated a substantial probability that the trade secret would otherwise be disclosed to the public during that proceeding and a substantial probability that the disclosure would cause serious harm to the owner of the secret, and where the court finds that there is no overriding public interest in an open proceeding. No evidence, however, shall be excluded during a criminal proceeding pursuant to this section if it would conceal a fraud, work an injustice, or deprive the People or the defendant of a fair trial.

(b) The motion made pursuant to subdivision (a) shall identify, without revealing, the trade secrets which would otherwise be disclosed to the public. A showing made pursuant to subdivision (a) shall be made during an in camera hearing with only the owner of the trade secret, the People’s representative, the defendant, and defendant’s counsel present. A court reporter shall be present during the hearing. Any transcription of the proceedings at the in camera hearing, as well as any articles presented at that hearing, shall be ordered sealed by the court and only a court may allow access to its contents upon a showing of good cause. The court, in ruling upon the motion made pursuant to subdivision (a), may consider testimony presented or affidavits filed in any proceeding held in that action.

(c) If, after the in camera hearing described in subdivision (b), the court determines that exclusion of trade secret information from the public is appropriate, the court shall close only that portion of the criminal proceeding necessary to prevent disclosure of the trade secret. Before granting the motion, however, the court shall find and state for the record that the moving party has met its burden pursuant to subdivision (b), and that the closure of that portion of the proceeding will not deprive the People or the defendant of a fair trial.

(d) The owner of the trade secret, the People, or the defendant may seek relief from a ruling denying or granting closure by petitioning a higher court for extraordinary relief.

(e) Whenever the court closes a portion of a criminal proceeding pursuant to this section, a transcript of that closed proceeding shall be made available to the public as soon as practicable. The court shall redact any information qualifying as a trade secret before making that transcript available.

(f) The court, subject to Section 867 of the Penal Code, may allow witnesses who are bound by a protective order entered in the criminal proceeding protecting trade secrets, pursaunt to Section 1061, to remain within the courtroom during the closed portion of the proceeding.