Local rules on amending a pleading, by county
All 58 counties, and most of them have nothing. Each entry says whether it was actually verified or not, because a confident wrong answer about local practice is worse than admitting the gap.
How to read the badges
Verified means a rule was found and read. Not verified means one was not, which is not the same as saying none exists.
Verified entries name a specific rule that was located and checked. There are only three: Los Angeles, San Francisco, Santa Cruz, plus Ventura, which is discussed below.
Not verified splits two ways. Some say a search was run and turned up no county rule on pleading amendment, which is a real finding and means the statewide framework governs. Others say only that the county was not checked for this page. Those are different claims and the tool keeps them apart on purpose.
Either way, local rules live on court websites and are not always indexed, and a direct-calendar or complex department layers its own standing orders on top of whatever the county publishes. Check both before you rely on any of this.
The one rule everyone should read
Ventura County Local Rule 4.07 states out loud the trap that catches people in every other county.
A proposed pleading attached to a "motion, application, or stipulation requesting leave, will not be deemed filed by the court." The amended pleading has to be presented to the clerk as a separate document, within the time the court specifies or within ten days of the order if it sets none.
That is true almost everywhere. Ventura is just the county that wrote it down. The copy attached to your stipulation is an exhibit, and if you never file the pleading itself you have an order granting leave and no operative complaint.
Complex departments are their own system
San Francisco General Order No. 55 established a master complaint and master answer regime for complex asbestos litigation. Los Angeles complex departments and JCCP proceedings issue standing orders that can require court approval before an amended pleading is filed at all.
If your case is in a complex department, the general order and the case management order set the amendment procedure, not the Code default.