diff --git a/libraries/Microsoft.Bot.Builder/Teams/TeamsActivityExtensions.cs b/libraries/Microsoft.Bot.Builder/Teams/TeamsActivityExtensions.cs
index 52113392a6..3d1452f6f0 100644
--- a/libraries/Microsoft.Bot.Builder/Teams/TeamsActivityExtensions.cs
+++ b/libraries/Microsoft.Bot.Builder/Teams/TeamsActivityExtensions.cs
@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+using System.Collections.Generic;
 using Microsoft.Bot.Schema;
 using Microsoft.Bot.Schema.Teams;
 
@@ -88,5 +89,16 @@ public static void TeamsNotifyUser(this IActivity activity)
         {
             activity.TeamsNotifyUser(false);
         }
+
+        /// <summary>
+        /// Gets the Teams OnBehalfOf list from the current activity.
+        /// </summary>
+        /// <param name="activity">The current activity.</param>
+        /// <returns>The current activity's OnBehalfOf list, or null.</returns>
+        public static IList<OnBehalfOf> TeamsGetTeamOnBehalfOf(this IActivity activity)
+        {
+            var channelData = activity.GetChannelData<TeamsChannelData>();
+            return channelData?.OnBehalfOf;
+        }
     }
 }
diff --git a/libraries/Microsoft.Bot.Schema/Teams/TeamsChannelData.cs b/libraries/Microsoft.Bot.Schema/Teams/TeamsChannelData.cs
index f9aa648e6f..f8aef4a470 100644
--- a/libraries/Microsoft.Bot.Schema/Teams/TeamsChannelData.cs
+++ b/libraries/Microsoft.Bot.Schema/Teams/TeamsChannelData.cs
@@ -29,12 +29,28 @@ public TeamsChannelData()
         /// <param name="tenant">Information about the tenant in which the
         /// message was sent.</param>
         public TeamsChannelData(ChannelInfo channel = default, string eventType = default, TeamInfo team = default, NotificationInfo notification = default, TenantInfo tenant = default)
+            : this(channel, eventType, team, notification, tenant, null)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TeamsChannelData"/> class.
+        /// </summary>
+        /// <param name="channel">Information about the channel in which the message was sent.</param>
+        /// <param name="eventType">Type of event.</param>
+        /// <param name="team">Information about the team in which the message was sent.</param>
+        /// <param name="notification">Notification settings for the message.</param>
+        /// <param name="tenant">Information about the tenant in which the
+        /// message was sent.</param>
+        /// <param name="onBehalfOf">The OnBehalfOf information of the message.</param>
+        public TeamsChannelData(ChannelInfo channel = default, string eventType = default, TeamInfo team = default, NotificationInfo notification = default, TenantInfo tenant = default, IList<OnBehalfOf> onBehalfOf = default)
         {
             Channel = channel;
             EventType = eventType;
             Team = team;
             Notification = notification;
             Tenant = tenant;
+            OnBehalfOf = onBehalfOf ?? new List<OnBehalfOf>();
             CustomInit();
         }
 
@@ -91,6 +107,13 @@ public TeamsChannelData(ChannelInfo channel = default, string eventType = defaul
         [JsonProperty(PropertyName = "settings")]
         public TeamsChannelDataSettings Settings { get; set; }
 
+        /// <summary>
+        /// Gets the OnBehalfOf list for user attribution.
+        /// </summary>
+        /// <value>The Teams activity OnBehalfOf list.</value>
+        [JsonProperty(PropertyName = "onBehalfOf")]
+        public IList<OnBehalfOf> OnBehalfOf { get; private set; }
+
         /// <summary>
         /// Gets or sets properties that are not otherwise defined by the <see cref="TeamsChannelData"/> type but that
         /// might appear in the REST JSON object.
diff --git a/tests/Microsoft.Bot.Builder.Tests/Teams/TeamsActivityExtensionsTests.cs b/tests/Microsoft.Bot.Builder.Tests/Teams/TeamsActivityExtensionsTests.cs
index 37f44e6f80..03b384b422 100644
--- a/tests/Microsoft.Bot.Builder.Tests/Teams/TeamsActivityExtensionsTests.cs
+++ b/tests/Microsoft.Bot.Builder.Tests/Teams/TeamsActivityExtensionsTests.cs
@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+using System;
+using System.Collections.Generic;
 using Microsoft.Bot.Schema;
 using Microsoft.Bot.Schema.Teams;
 using Xunit;
@@ -21,7 +23,7 @@ public void TeamsGetSelectedChannelId()
             // Assert
             Assert.Equal("channel123", channelId);
         }
-        
+
         [Fact]
         public void TeamsGetSelectedChannelIdNullSettings()
         {
@@ -130,5 +132,27 @@ public void TeamsNotifyUserExistingNotification()
             Assert.Equal(true, ((TeamsChannelData)activity.ChannelData).Notification.Alert);
             Assert.Equal("team123", ((TeamsChannelData)activity.ChannelData).Team.Id);
         }
+
+        [Fact]
+        public void TeamsChannelDataExistingOnBehalfOf()
+        {
+            // Arrange
+            var onBehalfOf = new OnBehalfOf
+            {
+                DisplayName = "TestOnBehalfOf",
+                ItemId = 0,
+                MentionType = "person",
+                Mri = Guid.NewGuid().ToString()
+            };
+
+            var activity = new Activity { ChannelData = new TeamsChannelData(onBehalfOf: new List<OnBehalfOf> { onBehalfOf }) };        
+
+            // Act
+            var onBehalfOfList = activity.TeamsGetTeamOnBehalfOf();
+
+            // Assert
+            Assert.Equal(1, onBehalfOfList.Count);
+            Assert.Equal("TestOnBehalfOf", onBehalfOfList[0].DisplayName);
+        }
     }
 }
diff --git a/tests/Microsoft.Bot.Schema.Tests/Teams/TeamsChannelDataTests.cs b/tests/Microsoft.Bot.Schema.Tests/Teams/TeamsChannelDataTests.cs
index 719f301a20..9f49c4a200 100644
--- a/tests/Microsoft.Bot.Schema.Tests/Teams/TeamsChannelDataTests.cs
+++ b/tests/Microsoft.Bot.Schema.Tests/Teams/TeamsChannelDataTests.cs
@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+using System;
+using System.Collections.Generic;
 using Microsoft.Bot.Schema.Teams;
 using Newtonsoft.Json.Linq;
 using Xunit;
@@ -19,7 +21,17 @@ public void TeamsChannelDataInits()
             var tenant = new TenantInfo("uniqueTenantId");
             var meeting = new TeamsMeetingInfo("BFSE Stand Up");
             var settings = new TeamsChannelDataSettings(channel);
-            var channelData = new TeamsChannelData(channel, eventType, team, notification, tenant)
+            var onBehalfOf = new List<OnBehalfOf>()
+            {
+                new OnBehalfOf() 
+                {
+                    DisplayName = "onBehalfOfTest",
+                    ItemId = 0,
+                    MentionType = "person",
+                    Mri = Guid.NewGuid().ToString()
+                }
+            };
+            var channelData = new TeamsChannelData(channel, eventType, team, notification, tenant, onBehalfOf)
             {
                 Meeting = meeting,
                 Settings = settings
@@ -34,6 +46,7 @@ public void TeamsChannelDataInits()
             Assert.Equal(tenant, channelData.Tenant);
             Assert.Equal(settings, channelData.Settings);
             Assert.Equal(channel, channelData.Settings.SelectedChannel);
+            Assert.Equal(onBehalfOf, channelData.OnBehalfOf);
         }
 
         [Fact]