Is it illegal for the property to send surveillance videos to the owners?

Legal analysis: the property sending surveillance video to the owner is an infringement of personal privacy and can be sued in court.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 165 Where an actor infringes upon the civil rights and interests of others through fault and causes damage, he shall bear tort liability. If the actor is presumed to be at fault according to the law and cannot prove that he is not at fault, he shall bear tort liability.

Article 166 Where an actor causes damage to the civil rights and interests of others, regardless of whether the actor is at fault or not, if the law stipulates that he should bear tort liability, such provisions shall prevail.