Is Viber sending legal?

Question

Law in IT

Good afternoon.
I am looking for information about the legality of Viber mailings.
Open source (bulletin board) where the target audience number data is located. If you collect these numbers and send out advertisements, then:
1. Is it legal?
2. How to automate the collection of numbers to make a mass mailing.

Answer 1

No, not legal.

Answer 2

Posting by the user of his number on the "bulletin board" does not mean consent to receive advertising information even from the bulletin board itself, not to mention advertising from third parties and organizations.
Moreover, the automated collection of numbers for advertising from absolutely any source is illegal in principle. It is necessary to obtain the user's personal consent to receive advertising from a specific organization to a specific user phone number. For example, some retail chains and other retailers achieve such consent by signing an agreement with the user on some kind of club card with accumulative points, it may contain a clause on consent to receive information about various promotions on the user's phone or even explicitly states that messengers.
I will add that if we are talking about the Viber Business Messages service, then such advertising is formally prohibited there, and mailing to randomly collected numbers in itself is guaranteed and very quickly leads to exceeding the threshold of 5% of complaints, according to which the service is immediately banned. For example, one such business immediately reached 80% of blocking, after long negotiations and oaths it was unbanned, but the service did not live long before the second ban.