What does "I don't know this person" do on LinkedIn?
When someone gets your invite, they can accept, ignore, or say they do not know you. That last option exists because LinkedIn asked members to connect with people they know. Using it is a vote that your request felt like spam from a stranger.
You do not get an email that says "Jane reported you." You infer it when limits tighten after a sloppy week, or when LinkedIn talks about invitations being marked as spam in its help articles. Treat every cold invite as something a busy stranger might flag.
The defense is not a cleverer opener. It is fewer, more relevant asks, a profile that looks like a colleague, and notes that do not pitch. If your accept rate is already low, you are closer to this button than you think.
Do not retaliate. Do not send a follow-up email that says "why did you ignore me." Withdraw stale pending invites so fewer people have a stale stranger request sitting in their queue where they might hit the flag later.
If you got a restriction after a campaign to a purchased list, assume IDK and ignores were part of it. Throw the list out. Build the next one from a trigger you can point at.
Frequently asked questions
It is specific to invitations. Messages and InMail have their own spam marks, which can also restrict sending. None of these are compliments.
LinkedIn does not publish a count. You do not want to find it. A handful on a small send volume is already a bad week.
That is the safest reading of the button. Most B2B outbound will still include people you have not met. Make the reason obvious so they do not feel tricked.
Treat IDK as a no. Do not keep a sequence running at them. Leave them alone.
Run the outreach from your own LinkedIn account
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