I'm wondering if it is legal for individuals or companies to use phonebook data for commercial purposes, such as contacting people found on the phone book to sell them products or services, or even selling that data to companies as leads so that they can contact them to try and sell their products/services.
From a GDPR perspective, I lean to conclude that people would have had to give their consent for their phone number to be used by companies to contact them, right? But it seems hard to find what did people sign and consented to by accepting on being listed on phonebooks.