diff --git a/types/google-publisher-tag/google-publisher-tag-tests.ts b/types/google-publisher-tag/google-publisher-tag-tests.ts
index daab32d7c6febd..0a01cb84e907f1 100644
--- a/types/google-publisher-tag/google-publisher-tag-tests.ts
+++ b/types/google-publisher-tag/google-publisher-tag-tests.ts
@@ -1,5 +1,5 @@
-// Tests for Google Publisher Tag 1.20260309
-// Synced from: https://github.com/googleads/google-publisher-tag-types/commit/b016c4944f367bc81fd32a072d0648154987849d
+// Tests for Google Publisher Tag 1.20260330
+// Synced from: https://github.com/googleads/google-publisher-tag-types/commit/9d3feab6f1efe54ba0195337deb1ec9e3557a5ca
 
 // Test for googletag.cmd
 function test_googletag_cmd() {
diff --git a/types/google-publisher-tag/index.d.ts b/types/google-publisher-tag/index.d.ts
index f65fde45470b27..535a689452c728 100644
--- a/types/google-publisher-tag/index.d.ts
+++ b/types/google-publisher-tag/index.d.ts
@@ -280,7 +280,8 @@ declare namespace googletag {
     function setConfig(config: config.PageSettingsConfig): void;
 
     /**
-     * Gets general configuration options for the page set by {@link setConfig}.
+     * Gets a frozen copy of the general configuration options for the page set by
+     * {@link setConfig}.
      *
      * Not all `setConfig()` properties are supported by this method. Supported
      * properties are:
@@ -296,11 +297,11 @@ declare namespace googletag {
      *   const config = googletag.getConfig(['adsenseAttributes', 'disableInitialLoad']);
      *
      * @param keys The keys of the configuration options to get.
-     * @return The configuration options for the slot.
+     * @return A frozen copy of the configuration options for the page.
      */
     function getConfig(
         keys: string | string[],
-    ): Pick<config.PageSettingsConfig, "adsenseAttributes" | "disableInitialLoad" | "targeting">;
+    ): Readonly<Pick<config.PageSettingsConfig, "adsenseAttributes" | "disableInitialLoad" | "targeting">>;
 
     /**
      * The command array accepts a sequence of functions and invokes them in
@@ -1685,11 +1686,13 @@ declare namespace googletag {
          * Sets general configuration options for this slot.
          *
          * @param slotConfig The configuration object.
+         * @return The slot object on which the method was called.
          */
-        setConfig(slotConfig: config.SlotSettingsConfig): void;
+        setConfig(slotConfig: config.SlotSettingsConfig): Slot;
 
         /**
-         * Gets general configuration options for the slot set by {@link setConfig}.
+         * Gets a frozen copy of the general configuration options for the slot set by
+         * {@link setConfig}.
          *
          * Not all `setConfig()` properties are supported by this method. Supported
          * properties are:
@@ -1707,11 +1710,11 @@ declare namespace googletag {
          *   const config = slot.getConfig(['adsenseAttributes', 'categoryExclusion']);
          *
          * @param keys The keys of the configuration options to get.
-         * @return The configuration options for the slot.
+         * @return A frozen copy of the configuration options for the slot.
          */
         getConfig(
             keys: string | string[],
-        ): Pick<config.SlotSettingsConfig, "categoryExclusion" | "targeting" | "adsenseAttributes">;
+        ): Readonly<Pick<config.SlotSettingsConfig, "categoryExclusion" | "targeting" | "adsenseAttributes">>;
     }
 
     /** Array of two numbers representing [width, height]. */
diff --git a/types/google-publisher-tag/package.json b/types/google-publisher-tag/package.json
index 2cbb64710f155d..a6205dfc27342f 100644
--- a/types/google-publisher-tag/package.json
+++ b/types/google-publisher-tag/package.json
@@ -1,7 +1,7 @@
 {
     "private": true,
     "name": "@types/google-publisher-tag",
-    "version": "1.20260309.9999",
+    "version": "1.20260330.9999",
     "nonNpm": "conflict",
     "nonNpmDescription": "Google Publisher Tag",
     "projects": [