diff --git a/CHANGES.ja.md b/CHANGES.ja.md
index cc1bfc9e0..804ae1a30 100644
--- a/CHANGES.ja.md
+++ b/CHANGES.ja.md
@@ -1,6 +1,14 @@
 変更点
 ======
 
+4.48 (未リリース)
+-----------------
+
+- `Service` クラス
+    * `isIdTokenDroppedOnIssueWithoutOpenid()` メソッドを追加。
+    * `setIdTokenDroppedOnIssueWithoutOpenid(boolean)` メソッドを追加。
+
+
 4.47 (2026 年 07 月 09 日)
 -----------------
 
diff --git a/CHANGES.md b/CHANGES.md
index 3f05fed0b..d438c9d2d 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,6 +1,14 @@
 CHANGES
 =======
 
+4.48 (Unreleased)
+-----------------
+
+- `Service` class
+    * Added the `isIdTokenDroppedOnIssueWithoutOpenid()` method.
+    * Added the `setIdTokenDroppedOnIssueWithoutOpenid(boolean)` method.
+
+
 4.47 (2026-07-09)
 -----------------
 
diff --git a/src/main/java/com/authlete/common/dto/Service.java b/src/main/java/com/authlete/common/dto/Service.java
index 5837ec016..1c75742c7 100644
--- a/src/main/java/com/authlete/common/dto/Service.java
+++ b/src/main/java/com/authlete/common/dto/Service.java
@@ -330,7 +330,7 @@
  */
 public class Service implements Serializable
 {
-    private static final long serialVersionUID = 93L;
+    private static final long serialVersionUID = 94L;
 
 
     /*
@@ -2103,6 +2103,18 @@ public class Service implements Serializable
     private boolean backchannelLogoutSessionSupported;
 
 
+    /**
+     * The flag indicating whether to refrain from issuing an ID token when the
+     * {@code openid} scope has been removed from the scopes to be granted by
+     * the {@code scopes} request parameter of the
+     * {@code /auth/authorization/issue} API.
+     *
+     * @since 4.48
+     * @since Authlete 3.0.36
+     */
+    private boolean idTokenDroppedOnIssueWithoutOpenid;
+
+
     /**
      * Get the service number.
      *
@@ -13965,4 +13977,70 @@ public Service setBackchannelLogoutSessionSupported(boolean supported)
 
         return this;
     }
+
+
+    /**
+     * Get the flag indicating whether to refrain from issuing an ID token when
+     * the {@code openid} scope has been removed from the scopes to be granted
+     * by the {@code scopes} request parameter of the
+     * {@code /auth/authorization/issue} API.
+     *
+     * <p>
+     * The {@code scopes} request parameter of the
+     * {@code /auth/authorization/issue} API can narrow down the scopes that
+     * were requested by the original authorization request. When the
+     * {@code openid} scope is removed in this way, the {@code scope} of the
+     * issued access token no longer contains {@code openid}, but, for
+     * historical reasons, an ID token is issued nevertheless.
+     * </p>
+     *
+     * <p>
+     * When this flag is {@code true}, no ID token is issued in that case, so
+     * that ID token issuance follows the granted {@code openid} scope. Flows
+     * whose {@code response_type} contains {@code id_token} are not affected,
+     * because the response type itself requires an ID token.
+     * </p>
+     *
+     * @return
+     *         {@code true} if no ID token is issued when the {@code openid}
+     *         scope has been removed by the {@code scopes} request parameter
+     *         of the {@code /auth/authorization/issue} API.
+     *
+     * @since 4.48
+     * @since Authlete 3.0.36
+     */
+    public boolean isIdTokenDroppedOnIssueWithoutOpenid()
+    {
+        return idTokenDroppedOnIssueWithoutOpenid;
+    }
+
+
+    /**
+     * Set the flag indicating whether to refrain from issuing an ID token when
+     * the {@code openid} scope has been removed from the scopes to be granted
+     * by the {@code scopes} request parameter of the
+     * {@code /auth/authorization/issue} API.
+     *
+     * <p>
+     * See the description of {@link #isIdTokenDroppedOnIssueWithoutOpenid()}
+     * for details.
+     * </p>
+     *
+     * @param dropped
+     *         {@code true} to refrain from issuing an ID token when the
+     *         {@code openid} scope has been removed by the {@code scopes}
+     *         request parameter of the {@code /auth/authorization/issue} API.
+     *
+     * @return
+     *         {@code this} object.
+     *
+     * @since 4.48
+     * @since Authlete 3.0.36
+     */
+    public Service setIdTokenDroppedOnIssueWithoutOpenid(boolean dropped)
+    {
+        this.idTokenDroppedOnIssueWithoutOpenid = dropped;
+
+        return this;
+    }
 }