diff --git a/function-app/adb-to-purview/src/Function.Domain/Constants/FeatureFlags.cs b/function-app/adb-to-purview/src/Function.Domain/Constants/FeatureFlags.cs
index b22e94b..85ed595 100644
--- a/function-app/adb-to-purview/src/Function.Domain/Constants/FeatureFlags.cs
+++ b/function-app/adb-to-purview/src/Function.Domain/Constants/FeatureFlags.cs
@@ -6,6 +6,10 @@ public static class FeatureFlags
         public static class Logging
         {
             public const string LogOlMessageToExternalStore = "LogOlMessageToExternalStore";
-        }                
+        }
+        public static class Security
+        {
+            public const string ValidateHttpOlSourceHeader = "ValidateHttpOlSourceHeader";
+        }
     }
 }
\ No newline at end of file
diff --git a/function-app/adb-to-purview/src/Function.Domain/Helpers/HttpHelper.cs b/function-app/adb-to-purview/src/Function.Domain/Helpers/HttpHelper.cs
index 5596aeb..098655b 100644
--- a/function-app/adb-to-purview/src/Function.Domain/Helpers/HttpHelper.cs
+++ b/function-app/adb-to-purview/src/Function.Domain/Helpers/HttpHelper.cs
@@ -1,6 +1,7 @@
 using System.Threading.Tasks;
 using System.Net;
 using Microsoft.Azure.Functions.Worker.Http;
+using System.Linq;
 
 namespace Function.Domain.Helpers
 {
@@ -19,5 +20,20 @@ public HttpResponseData CreateServerErrorHttpResponse(HttpRequestData req)
 
             return response;
         }
+
+        public HttpResponseData CreateUnauthorizedHttpResponse(HttpRequestData req)
+        {
+            var response = req.CreateResponse(HttpStatusCode.Forbidden);
+            return response;
+        }
+
+        public bool ValidateRequestHeaders(HttpRequestData req, string sourceHeaderExpectedValue)
+        {            
+            if (req.Headers.TryGetValues("x-teladoc-udf-ol-source", out var values))
+            {
+                return values.Contains(sourceHeaderExpectedValue, System.StringComparer.OrdinalIgnoreCase);
+            }
+            return false;
+        }
     }
 }
\ No newline at end of file
diff --git a/function-app/adb-to-purview/src/Function.Domain/Helpers/IHttpHelper.cs b/function-app/adb-to-purview/src/Function.Domain/Helpers/IHttpHelper.cs
index 4754efb..dd55f4e 100644
--- a/function-app/adb-to-purview/src/Function.Domain/Helpers/IHttpHelper.cs
+++ b/function-app/adb-to-purview/src/Function.Domain/Helpers/IHttpHelper.cs
@@ -7,5 +7,7 @@ public interface IHttpHelper
     {
          public Task<HttpResponseData> CreateSuccessfulHttpResponse(HttpRequestData req, object data);
          public HttpResponseData CreateServerErrorHttpResponse(HttpRequestData req);
+         public HttpResponseData CreateUnauthorizedHttpResponse(HttpRequestData req);
+         public bool ValidateRequestHeaders(HttpRequestData req, string sourceHeaderExpectedValue);
     }
 }
\ No newline at end of file
diff --git a/function-app/adb-to-purview/src/Functions/OpenLineageIn.cs b/function-app/adb-to-purview/src/Functions/OpenLineageIn.cs
index b78f72b..40977e8 100644
--- a/function-app/adb-to-purview/src/Functions/OpenLineageIn.cs
+++ b/function-app/adb-to-purview/src/Functions/OpenLineageIn.cs
@@ -54,7 +54,7 @@ public OpenLineageIn(
         [Function("OpenLineageIn")]
         public async Task<HttpResponseData> Run(
             [HttpTrigger(
-                AuthorizationLevel.Function,
+                AuthorizationLevel.Anonymous,
                 "get",
                 "post",
                 Route = "v1/lineage"
@@ -63,15 +63,24 @@ public async Task<HttpResponseData> Run(
             try
             {
                 _logger.LogInformation($"OpenLineageIn: Processing request...");
+
+                // Validate request headers
+                if (!_httpHelper.ValidateRequestHeaders(req, _configuration["OlSourceHeaderExpectedValue"] ?? Guid.NewGuid().ToString()))
+                {
+                    return _httpHelper.CreateUnauthorizedHttpResponse(req);
+                }
+
                 // send event data to EventHub
                 var events = new List<EventData>();
-
                 var strRequest = await req.ReadAsStringAsync();
+
+                // Validate body is not empty
                 if (string.IsNullOrEmpty(strRequest))
                 {
                     throw new Exception("OpenLineageIn: Request is null or empty.");
                 }
 
+                // Validate body is OpenLineage message
                 if (_olFilter.FilterOlMessage(strRequest))
                 {
                     _logger.LogInformation($"OpenLineageIn: Request passed validation.");