(a) Manner of application and service A party requesting a preliminary injunction may give notice of the request to the opposing or responding party either by serving a noticed motion under Code of Civil Procedure section 1005 or by obtaining and serving an order to show cause (OSC). An OSC must be used when a temporary restraining order (TRO) is sought, or if the party against whom the preliminary injunction is sought has not appeared in the action. If the responding party has not appeared, the OSC must be served in the same manner as a summons and complaint. (Subd (a) amended effective January 1, 2007; adopted effective July 1, 1997; previously amended effective July 1, 1999.)
Rule 3.1150.Preliminary injunctions and bonds
Division 11. Law and Motion · Chapter 3. Provisional and Injunctive Relief · Article 3. Injunctions · Last amended 2007 · Last verified July 29, 2026
In one sentenceRule 3.1150 governs how a party applies for a preliminary injunction in California superior court, covering notice by motion or order to show cause, filing the complaint or locating the court file, the required form of a TRO and OSC, personal attendance, disclosure of prior applications, and the undertaking that must follow a granted injunction.
Full Text of Rule 3.1150
(b) Filing of complaint or obtaining of court file If the action is initiated the same day a TRO or an OSC is sought, the complaint must be filed first. The moving party must provide a file-stamped copy of the complaint to the judge who will hear the application. If an application for a TRO or an OSC is made in an existing case, the moving party must request that the court file be made available to the judge hearing the application. (Subd (b) amended effective January 1, 2007; adopted effective July 1, 1997; previously amended effective July 1, 1999.)
(c) Form of OSC and TRO The OSC and TRO must be stated separately, with the OSC stated first. The restraining language sought in an OSC and a TRO must be separately stated in the OSC and the TRO and may not be incorporated by reference. The OSC must describe the injunction to be sought at the hearing. The TRO must describe the activities to be enjoined pending the hearing. A proposed OSC must contain blank spaces for the time and manner of service on responding parties, the date on which the proof of service must be delivered to the court hearing the OSC, a briefing schedule, and, if applicable, the expiration date of the TRO. (Subd (c) amended effective January 1, 2007; adopted effective July 1, 1997; previously amended effective July 1, 1999.)
(d) Personal attendance The moving party or counsel for the moving party must be personally present when the request for a TRO is made. (Subd (d) amended effective January 1, 2007; adopted as subd (e) effective July 1, 1997; amended as [Proof of service] effective July 1, 1999; previously relettered effective July 1, 1999.)
(e) Previous applications An application for a TRO or an OSC must state whether there has been any previous application for similar relief and, if so, the result of the application. (Subd (e) amended effective January 1, 2007; adopted as subd (f) effective July 1, 1997; previously amended and relettered effective July 1, 1999.)
(f) Undertaking Notwithstanding rule 3.1312, whenever an application for a preliminary injunction is granted, a proposed order must be presented to the judge for signature, with an undertaking in the amount ordered, within one court day after the granting of the application or within the time ordered. Unless otherwise ordered, any restraining order previously granted remains in effect during the time allowed for presentation for signature of the order of injunction and undertaking. If the proposed order and the undertaking required are not presented within the time allowed, the TRO may be vacated without notice. All bonds and undertakings must comply with rule 3.1130. (Subd (f) amended effective January 1, 2007; previously amended and relettered effective July 1, 1997.)
(g) Ex parte temporary restraining orders Applications for ex parte temporary restraining orders are governed by the ex parte rules in chapter 4 of this division. (Subd (g) amended effective January 1, 2007; adopted effective July 1, 1999.)
Plain-English Summary
Rule 3.1150 lays out the procedural path for seeking a preliminary injunction. A party can give notice the ordinary way, through a noticed motion under Code of Civil Procedure section 1005, or through an order to show cause. An OSC is not optional in two situations: when the party also wants a temporary restraining order, or when the party being targeted has not yet appeared in the case — in which case the OSC has to be served the same way a summons and complaint would be. If the case is being filed the same day the TRO or OSC is sought, the complaint has to be filed first, and the moving party brings a file-stamped copy to the judge; if the case already exists, the moving party instead has to make sure the court file itself is available at the hearing.
The rule is particular about format, too. The OSC and the TRO have to be set out as separate documents, in that order, and each has to describe on its own terms what it restrains — neither can just point back to the other by reference. A proposed OSC needs blank spaces for service details, a proof-of-service deadline, a briefing schedule, and, if there is a TRO involved, its expiration date. Whoever is asking for the TRO, or their attorney, has to show up in person when the request is made, and has to disclose whether a similar request has been made before and how it turned out.
Once a judge grants a preliminary injunction, the undertaking has to follow fast: a proposed order goes to the judge for signature, with the bond amount the court ordered, within one court day — or whatever other deadline the court sets — and any bond posted has to meet the requirements in Rule 3.1130. Any restraining order already in place stays in effect while that clock runs, but if the order and undertaking do not show up on time, the court can vacate the TRO without further notice. Ex parte requests for a TRO follow a separate track entirely, governed by the ex parte rules in chapter 4 of this division.
Frequently Asked Questions
When do I have to use an order to show cause instead of a regular noticed motion for a preliminary injunction?
Rule 3.1150(a) requires an OSC whenever the moving party also wants a temporary restraining order, or when the party the injunction is sought against has not yet appeared in the case.
How much time do I have to get the bond and proposed injunction order signed after the court grants my request?
One court day after the injunction is granted, or whatever different deadline the court sets. Rule 3.1150(f) also warns that if the order and undertaking are not presented in time, the court can vacate any TRO already in place without further notice.
Do I have to disclose that I already asked for a TRO once before and got denied?
Yes. Rule 3.1150(e) requires the application to state whether there has been a previous application for similar relief and what happened with it.
Do the OSC and the TRO need to be filed as one combined document?
No. Rule 3.1150(c) requires them to be stated separately, with the OSC listed first, and neither one may incorporate the other’s restraining language by reference.
Amendment History
Rule 3.1150 amended and renumbered effective January 1, 2007; adopted as rule 359 effective January 1, 1984; previously amended effective July 1, 1997, and July 1, 1999.
Source & verification. Rule text is reproduced verbatim from
the Judicial Council of California. Adopted by the Judicial Council of California.
Last verified July 29, 2026.
· Official source
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