diff --git a/api/openapi.yaml b/api/openapi.yaml
index 9f88116..25b7c7f 100644
--- a/api/openapi.yaml
+++ b/api/openapi.yaml
@@ -1256,7 +1256,7 @@ components:
         userId: 046b6c7f-0b8a-43b9-b35d-6489e6daee91
         parentId: 046b6c7f-0b8a-43b9-b35d-6489e6daee91
         referrer: referrer
-        isAnonymous: true
+        externalUserId: j0hn
         closeTime: 1
         campaign:
           name: name
@@ -1317,9 +1317,12 @@ components:
           format: uuid
           nullable: true
           type: string
-        isAnonymous:
-          description: The flag that indicates whether the user is anonymous.
-          type: boolean
+        externalUserId:
+          description: "The external user ID that is used to identify the user on\
+            \ the application side, unique across the workspace. It is always null\
+            \ for anonymous users."
+          nullable: true
+          type: string
         window:
           $ref: '#/components/schemas/Session_window'
         closeTime:
@@ -1361,7 +1364,7 @@ components:
           userId: 046b6c7f-0b8a-43b9-b35d-6489e6daee91
           parentId: 046b6c7f-0b8a-43b9-b35d-6489e6daee91
           referrer: referrer
-          isAnonymous: true
+          externalUserId: j0hn
           closeTime: 1
           campaign:
             name: name
@@ -1408,7 +1411,7 @@ components:
           userId: 046b6c7f-0b8a-43b9-b35d-6489e6daee91
           parentId: 046b6c7f-0b8a-43b9-b35d-6489e6daee91
           referrer: referrer
-          isAnonymous: true
+          externalUserId: j0hn
           closeTime: 1
           campaign:
             name: name
diff --git a/src/main/java/com/croct/client/export/model/Session.java b/src/main/java/com/croct/client/export/model/Session.java
index 2008709..3b856d4 100644
--- a/src/main/java/com/croct/client/export/model/Session.java
+++ b/src/main/java/com/croct/client/export/model/Session.java
@@ -45,7 +45,7 @@
   Session.JSON_PROPERTY_SESSION_ID,
   Session.JSON_PROPERTY_USER_ID,
   Session.JSON_PROPERTY_PARENT_ID,
-  Session.JSON_PROPERTY_IS_ANONYMOUS,
+  Session.JSON_PROPERTY_EXTERNAL_USER_ID,
   Session.JSON_PROPERTY_WINDOW,
   Session.JSON_PROPERTY_CLOSE_TIME,
   Session.JSON_PROPERTY_REFERRER,
@@ -67,8 +67,8 @@ public class Session {
   public static final String JSON_PROPERTY_PARENT_ID = "parentId";
   private JsonNullable<UUID> parentId = JsonNullable.<UUID>undefined();
 
-  public static final String JSON_PROPERTY_IS_ANONYMOUS = "isAnonymous";
-  private Boolean isAnonymous;
+  public static final String JSON_PROPERTY_EXTERNAL_USER_ID = "externalUserId";
+  private JsonNullable<String> externalUserId = JsonNullable.undefined();
 
   public static final String JSON_PROPERTY_WINDOW = "window";
   private SessionWindow window;
@@ -182,31 +182,32 @@ public void setParentId(UUID parentId) {
     this.parentId = JsonNullable.<UUID>of(parentId);
   }
 
+  /**
+   * The external user ID that is used to identify the user on the application side, unique across the workspace. It is always null for anonymous users.
+   * @return externalUserId
+   **/
+  @javax.annotation.Nullable
+  @JsonIgnore
 
-  public Session isAnonymous(Boolean isAnonymous) {
-    this.isAnonymous = isAnonymous;
-    return this;
+  public String getExternalUserId() {
+    return externalUserId.orElse(null);
   }
 
-   /**
-   * The flag that indicates whether the user is anonymous.
-   * @return isAnonymous
-  **/
-  @javax.annotation.Nullable
-  @JsonProperty(JSON_PROPERTY_IS_ANONYMOUS)
+  @JsonProperty(JSON_PROPERTY_EXTERNAL_USER_ID)
   @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
 
-  public Boolean getIsAnonymous() {
-    return isAnonymous;
+  public JsonNullable<String> getExternalUserId_JsonNullable() {
+    return externalUserId;
   }
 
-
-  @JsonProperty(JSON_PROPERTY_IS_ANONYMOUS)
-  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
-  public void setIsAnonymous(Boolean isAnonymous) {
-    this.isAnonymous = isAnonymous;
+  @JsonProperty(JSON_PROPERTY_EXTERNAL_USER_ID)
+  public void setExternalUserId_JsonNullable(JsonNullable<String> externalUserId) {
+    this.externalUserId = externalUserId;
   }
 
+  public void setExternalUserId(String externalUserId) {
+    this.externalUserId = JsonNullable.<String>of(externalUserId);
+  }
 
   public Session window(SessionWindow window) {
     this.window = window;
@@ -472,7 +473,7 @@ public boolean equals(Object o) {
     return Objects.equals(this.sessionId, session.sessionId) &&
         Objects.equals(this.userId, session.userId) &&
         equalsNullable(this.parentId, session.parentId) &&
-        Objects.equals(this.isAnonymous, session.isAnonymous) &&
+        Objects.equals(this.externalUserId, session.externalUserId) &&
         Objects.equals(this.window, session.window) &&
         Objects.equals(this.closeTime, session.closeTime) &&
         equalsNullable(this.referrer, session.referrer) &&
@@ -490,7 +491,7 @@ private static <T> boolean equalsNullable(JsonNullable<T> a, JsonNullable<T> b)
 
   @Override
   public int hashCode() {
-    return Objects.hash(sessionId, userId, hashCodeNullable(parentId), isAnonymous, window, closeTime, hashCodeNullable(referrer), hashCodeNullable(landingPageUrl), campaign, location, client, attributes, statistics);
+    return Objects.hash(sessionId, userId, hashCodeNullable(parentId), hashCodeNullable(externalUserId), window, closeTime, hashCodeNullable(referrer), hashCodeNullable(landingPageUrl), campaign, location, client, attributes, statistics);
   }
 
   private static <T> int hashCodeNullable(JsonNullable<T> a) {
@@ -507,7 +508,7 @@ public String toString() {
     sb.append("    sessionId: ").append(toIndentedString(sessionId)).append("\n");
     sb.append("    userId: ").append(toIndentedString(userId)).append("\n");
     sb.append("    parentId: ").append(toIndentedString(parentId)).append("\n");
-    sb.append("    isAnonymous: ").append(toIndentedString(isAnonymous)).append("\n");
+    sb.append("    externalUserId: ").append(toIndentedString(externalUserId)).append("\n");
     sb.append("    window: ").append(toIndentedString(window)).append("\n");
     sb.append("    closeTime: ").append(toIndentedString(closeTime)).append("\n");
     sb.append("    referrer: ").append(toIndentedString(referrer)).append("\n");