Resolve Duke uncertainty on public events

docs/RULE_DECISIONS.md

@@ -1,5 +1,12 @@
 # Rule decision index
 
+## Public resolution of Duke capture uncertainty — 29 October 2026
+
+A revealed ordinary Duke battle or named public revival, acquisition or death resolves the prior
+capture uncertainty; a later possible Harkonnen capture can restore it. This
+is a provisional online policy and does not infer legacy capture history.
+[Scope](ECAZ_DUKE_ACQUISITION.md#public-resolution-of-capture-uncertainty--29-october-2026).
+
 ## Duke Ambassador capture uncertainty — 29 October 2026
 
 Fresh games record whether a public capture could have involved Duke, without