California Code, Financial Code - FIN § 1570

(a) If the trust company's principal place of business is situated in a city the population of which does not exceed 100,000 persons, it shall deposit with the State Treasurer money or securities having a market value of at least fifty thousand dollars ($50,000) as security for the faithful performance and execution of all court trusts accepted by it, and money or securities having a market value of at least fifty thousand dollars ($50,000) as security for the faithful performance and execution of all private trusts accepted by it.

Whenever any such trust company receives trust funds or property, other than real property, from court trusts accepted by it to the amount of five hundred thousand dollars ($500,000), it shall forthwith give the commissioner written notice thereof, and within 30 days thereafter shall make an additional deposit with the State Treasurer of money or securities having a market value of fifty thousand dollars ($50,000) as security for its court trusts, and money or securities having a market value of fifty thousand dollars ($50,000) as additional security for its private trusts.

(b) If the trust company's principal place of business is situated in a city the population of which exceeds 100,000 persons, it shall deposit with the State Treasurer money or securities having a market value of at least one hundred thousand dollars ($100,000) as security for the faithful performance and execution of all court trusts accepted by it, and money or securities having a market value of at least one hundred thousand dollars ($100,000) as security for the faithful performance and execution of all private trusts accepted by it.