diff --git a/src/bot/chatProcedure.ts b/src/bot/chatProcedure.ts
index 20ff466..580a870 100644
--- a/src/bot/chatProcedure.ts
+++ b/src/bot/chatProcedure.ts
@@ -6,6 +6,7 @@ export interface ChatMessageEntry {
   text: string;
   timestamp: Date;
   source: 'chat';
+  isHistory: boolean;
 }
 
 /**
@@ -20,7 +21,7 @@ export class ChatProcedure {
   private _onChatMessage: (entry: ChatMessageEntry) => void;
   private _isSubscribed: boolean = false;
   private _lastMessageText: string = '';
-  private _chatReadyAtMs: number = 0;
+  private _botJoinedAtMs: number = 0;
   private _recentMessageKeyTimestamps: Map<string, number> = new Map();
 
   constructor(
@@ -33,6 +34,14 @@ export class ChatProcedure {
     this._onChatMessage = onChatMessage;
   }
 
+  /**
+   * Set the bot's join timestamp so we can classify messages as history vs live.
+   */
+  setBotJoinedAt(ms: number): void {
+    this._botJoinedAtMs = ms;
+    this._logger.info(`Chat history cutoff set: messages before ${new Date(ms).toISOString()} are history`);
+  }
+
   /**
    * Open the chat panel and start monitoring messages.
    */
@@ -121,6 +130,7 @@ export class ChatProcedure {
         speaker: string;
         text: string;
         timestamp: string;
+        teamsTimestamp?: string;
         messageKey?: string;
       }) => {
         this._handleChatMessage(msg);
@@ -156,8 +166,26 @@ export class ChatProcedure {
         return noisePatterns.some(p => lower.includes(p));
       }
 
+      function _extractTeamsTimestamp(el: HTMLElement): string | undefined {
+        const timeSelectors = [
+          'time[datetime]',
+          '[data-tid="message-timestamp"] time',
+          '[data-tid*="timestamp"] time',
+          '[data-tid="message-timestamp"]',
+        ];
+        for (const sel of timeSelectors) {
+          const timeEl = el.querySelector(sel) || el.closest?.('[data-tid*="message"]')?.querySelector(sel);
+          if (timeEl) {
+            const dt = timeEl.getAttribute('datetime');
+            if (dt) return dt;
+            const title = timeEl.getAttribute('title');
+            if (title) return title;
+          }
+        }
+        return undefined;
+      }
+
       function _extractChatMessage(el: HTMLElement): boolean {
-        // Strategy 1: Standard selectors
         const messageSelectors = [
           '[data-tid="chat-message"]',
           '.fui-ChatMessage',
@@ -203,10 +231,12 @@ export class ChatProcedure {
           }
 
           if (text && text.length > 0) {
+            const teamsTs = _extractTeamsTimestamp(messageEl) || _extractTeamsTimestamp(el);
             (window as any).__onChatMessageEvent({
               speaker: author,
               text,
-              timestamp: new Date().toISOString(),
+              timestamp: teamsTs || new Date().toISOString(),
+              teamsTimestamp: teamsTs,
               messageKey: `${author}::${text}`,
             });
             return true;
@@ -239,10 +269,12 @@ export class ChatProcedure {
               // Check if this looks like a time-stamped message (not just any two children)
               const hasTid = children[i].getAttribute('data-tid') || '';
               if (hasTid.includes('author') || hasTid.includes('name') || hasTid.includes('sender')) {
+                const teamsTs = _extractTeamsTimestamp(el);
                 (window as any).__onChatMessageEvent({
                   speaker: candidateName,
                   text: candidateBody,
-                  timestamp: new Date().toISOString(),
+                  timestamp: teamsTs || new Date().toISOString(),
+                  teamsTimestamp: teamsTs,
                   messageKey: `${candidateName}::${candidateBody}`,
                 });
                 return true;
@@ -325,19 +357,21 @@ export class ChatProcedure {
     });
 
     this._logger.info(`Chat MutationObserver set up (target: ${chatObserverTarget})`);
-    // Guard against Teams replaying historical thread entries as fresh mutations.
-    this._chatReadyAtMs = Date.now() + 12000;
-    this._logger.info('Chat monitor warmup active for 12s');
   }
 
   /**
    * Handle a chat message event from the browser.
    */
-  private _handleChatMessage(msg: { speaker: string; text: string; timestamp: string; messageKey?: string }): void {
+  private _handleChatMessage(msg: {
+    speaker: string;
+    text: string;
+    timestamp: string;
+    teamsTimestamp?: string;
+    messageKey?: string;
+  }): void {
     if (!this._isSubscribed || !msg.text) return;
 
     const nowMs = Date.now();
-    if (this._chatReadyAtMs > 0 && nowMs < this._chatReadyAtMs) return;
 
     // Dedup
     if (msg.text === this._lastMessageText) return;
@@ -353,13 +387,22 @@ export class ChatProcedure {
     }
     this._lastMessageText = msg.text;
 
-    this._logger.info(`Chat: [${msg.speaker}] ${msg.text}`);
+    // Classify as history (sent before bot joined) vs live
+    const messageTimestamp = new Date(msg.teamsTimestamp || msg.timestamp);
+    const messageMs = messageTimestamp.getTime();
+    const isHistory = this._botJoinedAtMs > 0 && messageMs < this._botJoinedAtMs;
+
+    this._logger.info(
+      `Chat${isHistory ? ' [HISTORY]' : ''}: [${msg.speaker}] ${msg.text}` +
+      (msg.teamsTimestamp ? ` (teams_ts=${msg.teamsTimestamp})` : ''),
+    );
 
     this._onChatMessage({
       speaker: msg.speaker,
       text: msg.text,
-      timestamp: new Date(msg.timestamp),
+      timestamp: messageTimestamp,
       source: 'chat',
+      isHistory,
     });
   }
 
diff --git a/src/bot/orchestrator.ts b/src/bot/orchestrator.ts
index 28dc1ae..ee1cee2 100644
--- a/src/bot/orchestrator.ts
+++ b/src/bot/orchestrator.ts
@@ -1025,8 +1025,7 @@ export class BotOrchestrator {
       this._page,
       this._logger,
       (entry: ChatMessageEntry) => {
-        // Send chat message to Gateway as a special transcript
-        this._sendChatMessage(entry.speaker, entry.text);
+        this._sendChatMessage(entry.speaker, entry.text, entry.isHistory);
         this._callbacks.onTranscript({
           speaker: entry.speaker,
           text: entry.text,
@@ -1203,6 +1202,7 @@ export class BotOrchestrator {
    */
   private async _enableChat(): Promise<void> {
     try {
+      this._chatProcedure!.setBotJoinedAt(Date.now());
       await this._chatProcedure!.enableChatMonitoring();
       await this._chatProcedure!.subscribeToChatMessages();
       this._logger.info('Chat monitoring enabled and subscribed');
@@ -1252,7 +1252,7 @@ export class BotOrchestrator {
   /**
    * Send a chat message event to the Gateway.
    */
-  private _sendChatMessage(speaker: string, text: string): void {
+  private _sendChatMessage(speaker: string, text: string, isHistory: boolean = false): void {
     const message: ChatMessage = {
       type: 'chatMessage',
       sessionId: this._sessionId,
@@ -1260,6 +1260,7 @@ export class BotOrchestrator {
         speaker,
         text,
         timestamp: new Date().toISOString(),
+        isHistory,
       },
     };
     this._sendToGateway(message);
diff --git a/src/types/index.ts b/src/types/index.ts
index 3d71dfb..c97e461 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -47,6 +47,7 @@ export interface ChatMessage {
     speaker: string;
     text: string;
     timestamp: string;
+    isHistory?: boolean;
   };
 }