diff --git a/frontend/src/app/universe/multichain-explorer/chain-reasons.spec.ts b/frontend/src/app/universe/multichain-explorer/chain-reasons.spec.ts
index 170f4c1bba..230ca58aab 100644
--- a/frontend/src/app/universe/multichain-explorer/chain-reasons.spec.ts
+++ b/frontend/src/app/universe/multichain-explorer/chain-reasons.spec.ts
@@ -17,6 +17,12 @@ describe('describeChainReason', () => {
     // faults they describe an outage that is not happening.
     expect(describeChainReason('pending-protocol-coverage-unavailable').kind).toBe('limit');
     expect(describeChainReason('reorg-evidence-tail-only').kind).toBe('limit');
+    // The backend derives these from the authority's published coverage
+    // dimensions, so each one must read as a stated limit rather than fall
+    // through to the unstated wording.
+    expect(describeChainReason('pending-protocol-coverage-partial').kind).toBe('limit');
+    expect(describeChainReason('pending-protocol-coverage-unknown').kind).toBe('limit');
+    expect(describeChainReason('reorg-evidence-unknown').kind).toBe('limit');
     expect(describeChainReason('protocol-authority-unavailable').kind).toBe('fault');
   });
 
diff --git a/frontend/src/app/universe/multichain-explorer/chain-reasons.ts b/frontend/src/app/universe/multichain-explorer/chain-reasons.ts
index 97537adebe..7a0ff7b3bc 100644
--- a/frontend/src/app/universe/multichain-explorer/chain-reasons.ts
+++ b/frontend/src/app/universe/multichain-explorer/chain-reasons.ts
@@ -123,6 +123,18 @@ const REASON_COPY: Record<string, ReasonCopy> = {
     text: $localize`:@@universe.reason.reorg-evidence-tail-only:This authority keeps reorganisation evidence for recent blocks only, not for the whole chain.`,
     kind: 'limit',
   },
+  'pending-protocol-coverage-partial': {
+    text: $localize`:@@universe.reason.pending-protocol-coverage-partial:This authority sees some pending transactions but not all of them, so a missing one does not mean it does not exist.`,
+    kind: 'limit',
+  },
+  'pending-protocol-coverage-unknown': {
+    text: $localize`:@@universe.reason.pending-protocol-coverage-unknown:This authority has not stated what pending coverage it offers, so none is assumed.`,
+    kind: 'limit',
+  },
+  'reorg-evidence-unknown': {
+    text: $localize`:@@universe.reason.reorg-evidence-unknown:This authority has not stated what reorganisation evidence it keeps, so none is assumed.`,
+    kind: 'limit',
+  },
   'protocol-qualification-pending': {
     text: $localize`:@@universe.reason.protocol-qualification-pending:Protocol qualification has not been established.`,
     kind: 'fault',