How to identify linked user accounts?

Question

Algorithms

There is a DB with physical. and legal persons. Addresses, phone numbers, personal data, email, etc. are indicated. What methods can be used to determine that a site user uses several accounts for work and link them in the database?
Cookies: IPs won't help if it comes from different browsers
: there can be many users on the same IP
. address: Again, there can be several companies in the same building.
Help me decide on some kind of tracking algorithm.

Answer 1

There is a DB with physical. and legal persons. Addresses, phone numbers, personal data, email, etc. are indicated. What methods can be used to determine that a site user uses several accounts for work and link them in the database?

In this scenario, in my opinion, there are 2 options. Either by indirect signs (write a system for analyzing everything at once, Cookies, IPs, addresses, etc., which would tie everything together and give a certain percentage of the probability that the user belongs to one group or another /company), or you can ask the users themselves what company they belong to.