What signals the system watches for

Acted on

• A job change or promotion, detected from a change in someone's professional headline.
• A new post, provided it has genuine content. Contact cards, link drops, job adverts and one-line slogans are filtered out.
• A connection request being accepted, but only when it is genuinely recent.

Deliberately ignored

• Someone viewing your profile. Messaging about it reads as desperate.
• A like or a reaction. That is acknowledgement, not interest.
• Work anniversaries. Congratulating someone for not leaving is a well known automation tell.
• Birthdays, unless you actually know the person.
• A headline that was reworded rather than genuinely changed.

On job change detection

LinkedIn does not tell third parties when someone changes job, so it is inferred from headline changes. The system is deliberately cautious: it looks for a change of employer, a change in seniority, or explicit language about starting somewhere new. A reworded headline is treated as no change at all.

Where it cannot tell, the draft is held for your review rather than sent, because congratulating someone on a job they did not start is worse than staying quiet.