diff --git a/services/imessage-bridge/src/session.ts b/services/imessage-bridge/src/session.ts
index 5ec00c74..c0219aaf 100644
--- a/services/imessage-bridge/src/session.ts
+++ b/services/imessage-bridge/src/session.ts
@@ -7373,7 +7373,12 @@ export class IMessageSession {
     // PROACTIVE INGESTER (unknown senders): appointment confirmations →
     // surface to the owner + offer to add to the calendar; marketing/spam →
     // suppress (no auto-reply). Behind LANTERN_APPT_INGEST (default on).
-    const ingest = await this.maybeIngestUnknownInbound(row.handle, text).catch(() => "pass" as const);
+    // DM-only, matching every sibling proactive-scan block above and the
+    // WhatsApp equivalent (isGroupJid guard) — a group participant's message
+    // is never an "unknown sender" appointment confirmation to swallow.
+    const ingest = !isGroup
+      ? await this.maybeIngestUnknownInbound(row.handle, text).catch(() => "pass" as const)
+      : ("pass" as const);
     if (ingest === "handled") {
       // No silent drops: an unknown-inbound message owned by the life-event /
       // appointment ingester means the CONTACT got no auto-reply. Leave a trace
diff --git a/services/imessage-bridge/src/unknown-inbound-group-scope.test.ts b/services/imessage-bridge/src/unknown-inbound-group-scope.test.ts
new file mode 100644
index 00000000..a3e01c09
--- /dev/null
+++ b/services/imessage-bridge/src/unknown-inbound-group-scope.test.ts
@@ -0,0 +1,27 @@
+import { describe, it, expect } from "vitest";
+import { readFileSync } from "node:fs";
+
+// Regression: PROACTIVE INGESTER (maybeIngestUnknownInbound) is designed for
+// unknown 1:1 senders ("appointment confirmations from an unrecognized
+// number"), but its iMessage call site had no !isGroup guard — unlike every
+// sibling proactive-scan block in this file (style-learning, inner-circle
+// agentic, proactive-memory) and unlike the WhatsApp bridge's own
+// maybeIngestUnknownInbound (`!this.isGroupJid(from)`). A group participant's
+// message pattern-matching delivery/appointment language got silently
+// swallowed — "contact reply suppressed — unknown-inbound owned by
+// life-event/appointment ingestion" — inside live GROUP threads, confirmed
+// live 2026-08-18 (chatRowid 2656, isGroup:true) and reconfirmed repeatedly.
+// This only fixes the group-scope leak; whether a genuine 1:1 unknown-sender
+// appointment text should ever get a contact-facing reply is a separate,
+// still-open product question (introspect state.json).
+
+describe("maybeIngestUnknownInbound call site is DM-only", () => {
+  const src = readFileSync(new URL("./session.ts", import.meta.url), "utf8");
+
+  it("the call site checks !isGroup before invoking the ingester", () => {
+    const anchor = "const ingest = ";
+    const site = src.slice(src.indexOf(anchor), src.indexOf(anchor) + 300);
+    expect(site).toMatch(/!isGroup/);
+    expect(site).toMatch(/maybeIngestUnknownInbound/);
+  });
+});