Legal Question in Real Estate Law in California

They obviously think they do, and they make their rules. However, if the lien on your property is not legitimately supported in law or fact, you can file suit to 'clear title'. Without knowing all the facts, and reviewing all the documents involved, no one can give you an intelligent opinion as to your 'rights'. If serious about hiring counsel to review and advise you, feel free to contact me to arrange.

Without knowing what the lien is for, there is no way to be sure. Most likely, however, since you are talking about thousands of properties, it is a lien for some form of tax or assessment. If so, your tax/assessment bill is notice of the lien which automatically attaches along with the bill as a matter of law.