Did the property company infringe the owner's mobile phone number?

Infringement. According to the provisions of China's Civil Code, the personal information of natural persons is protected by law. Any organization or individual who needs to obtain other people's personal information shall obtain and ensure the information security according to law, and shall not illegally collect, use, process or transmit other people's personal information, or illegally buy, sell, provide or disclose other people's personal information. Therefore, if a property company sells personal information such as the owner's mobile phone number, it constitutes infringement. According to Article 111th of the Civil Law of People's Republic of China (PRC), the personal information of natural persons is protected by law. Any organization or individual who needs to obtain other people's personal information shall obtain and ensure the information security according to law, and shall not illegally collect, use, process or transmit other people's personal information, or illegally buy, sell, provide or disclose other people's personal information.