How do ARC chains validate?

A receiver checks:

• Whether each ARC set has a valid instance number (i=) in ascending order.
• Whether each ARC Seal (AS) correctly signs the previous hop’s ARC data.
• Whether any hop altered earlier AAR or AMS records.
• Whether the chain ends with a valid final seal.
• Whether the signer domains are trusted.

A valid chain signals trustworthy forwarding and results in a Chain Validation status of cv=pass. Broken chains often return cv=fail.