CAIN-42 invariant · E28

E28-I80: renewal re-signs against the current identity and policy

Held · CAIN-42 Evolution 28 -- Portable Machine Agency & Execution Identity

Last reviewed 2026-10-01

held niche Identity, authority & delegation · family lease

What this rule means

CAIN-42 must always satisfy: renewal re-signs against the current identity and policy. It is one of 90 invariants checked for CAIN-42 Evolution 28 -- Portable Machine Agency & Execution Identity. An invariant is a rule the system may never break, whatever an agent or attacker does; the test suite tries to break it across many scenarios and records the result.

Recorded detail

['LEASE_SPONSOR_KEY_MISMATCH']

Verify it in your browser

Your browser downloads the bundle's SHA256SUMS manifest and the file(s) behind this page, hashes them with SHA-256 locally (WebCrypto), and compares. A match shows the record you are reading is the published one; it does not by itself prove who published it (see the signed claims registry and the bundle verifier for that).

Check it yourself

Browse the raw bundle · How to reproduce it · SHA-256 manifest

Scope: E28 is an in-process library. It is not wired into the hosted gateway, MCPGate or the PBFT clusters; nothing on the three public sites runs it live.

Related rules

E28-I33: a key already bound to an identity cannot register again (clone)
E28-I35: declaring an unregistered capability is refused
E28-I52: an unknown delegation dimension is refused
E28-I53: an omitted dimension is inherited, never widened
E28-I54: a parent without downstream delegation cannot delegate
E28-I55: delegation beyond max depth is refused
E28-I56: a child cannot outlive its parent
E28-I57: a tampered delegation token is detected in the chain

← E28-I79 · all 90 · E28-I81 →

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