I never had a LinkedIn account but was getting email from them. Hitting the unsubscribe button would stop it for a month but then restart again. After about 6 m

I never had a LinkedIn account but was getting email from them. Hitting the unsubscribe button would stop it for a month but then restart again. After about 6 months I sent them a mail threatening legal action if I ever received a mail from them again, and since then it’s been blissfully quiet. They must have an internal black-list for people that do that.