diff --git a/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md b/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
index 7562b147..4428779f 100644
--- a/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
+++ b/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
@@ -680,3 +680,7 @@ names the principle that settles it, and is cited as "design 47 G A-n".
   them, since the grants part composes a verb's call subject only for the callers its effective list names, so the
   bus holds the rest out. `seatdef.DefaultCallers` follows §610 (act, warrant and accept: operator, sessions and
   invokers).
+- **A-180** (§64, §420, A-160, A-174; principles 1 and 7) The runner places a run's pipelines when it hears the
+  catalog seat's `catalog-revision` for the candidate `run-<id>` (a candidate's revision, its subject naming it),
+  reading the candidate's entries and fingerprints through the seat's `revision` verb with the candidate's group;
+  `<id>` is a random 12-hex id the runner makes, so two runs of one commit are two pipelines.