Legal Question in Real Estate Law in California

You do not seem to understand jurisdiction. Jurisdiction is geographical. A state court has jurisdiction over all property within the geographic area it serves and governs. It also has jurisdiction over anyone living within that geographic area and anyone with sufficient business or legal contacts with that area to make it reasonable and just for the court to assert jurisdiction over them. Owning property in that geographic area would be a classic example of something that would give a court jurisdiction over a person who doesn't live in the jurisdictional area. It's a little more complicated when it comes to federal court jurisdiction but mostly the same. So if the property was within the court's geographic jurisdiction the court had jurisdiction over it and anyone having or claimg ownership of it.

Yes, a court has jurisdiction to decide who owns real property. It is not jurisdiction over the property that is as important as jurisdiction over the parties. If you were a party to the case and the decision was against you, you should contact an attorney that handles appeals. If you were not a party, you should consult with an attorney. It is possible that the decision could be vacated. Move quickly. There is limited time to take action.

A court MAY have jurisdiction to decide who owns real property. If the real property is in California, a Nevada court won't have jurisdiction. This type of jurisdiction is called "territorial" jurisdiction. Next, if "X" is the owner and X hasn't been served with process, the court lacks jurisdiction to decide against X -- that's called "personal" jurisdiction. Finally, there is "subject matter" jurisdiction, i.e., a criminal court or a small claims court probably lacks jurisdiction to hear and decide civil matters like ownership of real estate. So, if the real property is in California, jurisdiction will depend upon the court being the civil division of a California state superior court and the defendant(s) being properly served. Otherwise, a lack of jurisdiction is very probably present.