(a) Decision on complex designation Except as provided in rule 3.402, if a Civil Case Cover Sheet (form CM-010) that has been filed and served designates an action as a complex case or checks a case type described as provisionally complex civil litigation, the court must decide as soon as reasonably practicable, with or without a hearing, whether the action is a complex case. (Subd (a) amended effective January 1, 2007; previously amended effective July 1, 2004.)
Rule 3.403.Action by court
Division 4. Parties and Actions · Chapter 5. Complex Cases · Last amended 2007 · Last verified July 29, 2026
In one sentenceRule 3.403 requires a court to decide, as soon as reasonably practicable, whether a case marked complex on its cover sheet truly is a complex case, and it gives the court continuing authority to change that determination later, on its own motion or a party's noticed motion.
Full Text of Rule 3.403
(b) Court’s continuing power With or without a hearing, the court may decide on its own motion, or on a noticed motion by any party, that a civil action is a complex case or that an action previously declared to be a complex case is not a complex case.
Plain-English Summary
Designations and counterdesignations only get a case so far — someone still has to make the call. Rule 3.403 puts that job on the court itself. Once a filed and served cover sheet marks a case complex, or checks a case type described as provisionally complex, the court must decide, as soon as reasonably practicable and with or without a hearing, whether the case truly qualifies as complex under rule 3.400. That obligation gives way to rule 3.402's own 30-day process when a counterdesignation is on the table.
The court's authority does not end with that first decision. Rule 3.403(b) lets the court revisit the question at any time, on its own motion or a party's noticed motion, and with or without a hearing, so a case that turns out to be simpler than expected can be moved off the complex track, and a case that grows more complicated can be moved onto it.
Frequently Asked Questions
How quickly must a court decide whether a case is complex?
Rule 3.403(a) requires the court to decide as soon as reasonably practicable, with or without a hearing, once a filed and served cover sheet designates the case complex.
Can a court change its mind about complex case status later in the litigation?
Yes. Rule 3.403(b) gives the court continuing power to decide, on its own motion or a party's noticed motion, that a case is or is no longer complex.
Does Rule 3.403 apply when a defendant has filed a counterdesignation?
Amendment History
Rule 3.403 amended effective January 1, 2007; adopted as rule 1812 effective January 1, 2000; previously amended effective July 1, 2004; previously amended and renumbered effective January 1, 2007.
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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