A delegation is not a proof you carry. You hold authority only while an unbroken chain of live delegations runs from the subject to you, and the verifier finds that chain by searching the whole set.

This is the one design decision the rest of Keyline follows from: late binding, cascade, revival, and order independence are all consequences.

In most systems, a credential is a ticket. You show it at the door, and the door checks the ticket itself. The ticket carries its own proof.

A Keyline delegation carries no proof. It says who signed it, who it is for, what it is about, and how much power. That is all.

So how is it checked? Picture the document as a wall socket. Each delegation is a power strip, plugged into another strip.

You have power if current reaches you. It flows out of the socket, through every strip, to your device. Not because your strip says so. Because current arrives.

Bob can plug Carol in before Bob has any power. Her cord just sits there, dark. The moment someone plugs Bob in, Carol lights up. Nothing is re-signed.

Unplug Bob, and Carol goes dark. Her certificate did not change. It is not revoked. It is dead. No current reaches it.

Plug Bob back in, and Carol returns. Same certificate. Same signature.

Junk is harmless. A ring of strips with no path to the wall carries nothing. Anyone can sign anything. Only routes matter.

A certificate is never valid or invalid on its own. It is live or dead, in the context of the whole bag.

Check yourself. Bob signs a delegation to Carol while Bob himself has no access. What happens when Bob is later given access?