Legal and Ethical Aspect of Emailing Users Who Didn't Opt-In?

[VisEntities]

I'm curious about the legal and ethical aspects of sending emails to users who didn't opt in to receive them. Would it generally be ignored, or could there be serious repercussions? Has anyone in internet history ever taken an action over receiving an unwanted email, aside from just unsubscribing?

Thanks!
Legal and Ethical Aspect of Emailing Users Who Didn't Opt-In?

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