Chapter 2. Jurisdiction And Venue of California Probate Code >> Division 4.5. >> Part 4. >> Chapter 2.

(a) The superior court has jurisdiction in proceedings under this division.
  (b) The court in proceedings under this division is a court of general jurisdiction and the court, or a judge of the court, has the same power and authority with respect to the proceedings as otherwise provided by law for a superior court, or a judge of the superior court, including, but not limited to, the matters authorized by Section 128 of the Code of Civil Procedure.

The court may exercise jurisdiction in proceedings under this division on any basis permitted by Section 410.10 of the Code of Civil Procedure.

Without limiting Section 4521, a person who acts as an attorney-in-fact under a power of attorney governed by this division is subject to personal jurisdiction in this state with respect to matters relating to acts and transactions of the attorney-in-fact performed in this state or affecting property or a principal in this state.

The proper county for commencement of a proceeding under this division shall be determined in the following order of priority:
  (a) The county in which the principal resides.
  (b) The county in which the attorney-in-fact resides.
  (c) A county in which property subject to the power of attorney is located.
  (d) Any other county that is in the principal's best interest.