diff --git a/dlls/shdocvw/persist.c b/dlls/shdocvw/persist.c
index b4fecbbfe35..940dd16dd11 100644
--- a/dlls/shdocvw/persist.c
+++ b/dlls/shdocvw/persist.c
@@ -92,8 +92,6 @@ static HRESULT WINAPI PersistStorage_SaveCompleted(IPersistStorage *iface, LPSTO
     return E_NOTIMPL;
 }
 
-#define PERSTORAGE_THIS(ifce) DEFINE_THIS(WebBrowser, PersistStorage, iface)
-
 static const IPersistStorageVtbl PersistStorageVtbl =
 {
     PersistStorage_QueryInterface,
@@ -107,6 +105,87 @@ static const IPersistStorageVtbl PersistStorageVtbl =
     PersistStorage_SaveCompleted
 };
 
+/**********************************************************************
+ * Implement the IPersistMemory interface
+ */
+
+#define PERMEMORY_THIS(ifce) DEFINE_THIS(WebBrowser, PersistMemory, iface)
+
+static HRESULT WINAPI PersistMemory_QueryInterface(IPersistMemory *iface,
+        REFIID riid, LPVOID *ppobj)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    return IWebBrowser_QueryInterface(WEBBROWSER(This), riid, ppobj);
+}
+
+static ULONG WINAPI PersistMemory_AddRef(IPersistMemory *iface)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    return IWebBrowser_AddRef(WEBBROWSER(This));
+}
+
+static ULONG WINAPI PersistMemory_Release(IPersistMemory *iface)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    return IWebBrowser_Release(WEBBROWSER(This));
+}
+
+static HRESULT WINAPI PersistMemory_GetClassID(IPersistMemory *iface, CLSID *pClassID)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    FIXME("(%p)->(%p)\n", This, pClassID);
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI PersistMemory_IsDirty(IPersistMemory *iface)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    FIXME("(%p)\n", This);
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI PersistMemory_InitNew(IPersistMemory *iface)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    FIXME("(%p)\n", This);
+    return S_OK;
+}
+
+static HRESULT WINAPI PersistMemory_Load(IPersistMemory *iface, LPVOID pMem, ULONG cbSize)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    FIXME("(%p)->(%p %x)\n", This, pMem, cbSize);
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI PersistMemory_Save(IPersistMemory *iface, LPVOID pMem,
+        BOOL fClearDirty, ULONG cbSize)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    FIXME("(%p)->(%p %x %x)\n", This, pMem, fClearDirty, cbSize);
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI PersistMemory_GetSizeMax(IPersistMemory *iface, ULONG *pCbSize)
+{
+    WebBrowser *This = PERMEMORY_THIS(iface);
+    FIXME("(%p)->(%p)\n", This, pCbSize);
+    return E_NOTIMPL;
+}
+
+static const IPersistMemoryVtbl PersistMemoryVtbl =
+{
+    PersistMemory_QueryInterface,
+    PersistMemory_AddRef,
+    PersistMemory_Release,
+    PersistMemory_GetClassID,
+    PersistMemory_IsDirty,
+    PersistMemory_Load,
+    PersistMemory_Save,
+    PersistMemory_GetSizeMax,
+    PersistMemory_InitNew
+};
+
 /**********************************************************************
  * Implement the IPersistStreamInit interface
  */
@@ -192,5 +271,6 @@ static const IPersistStreamInitVtbl PersistStreamInitVtbl =
 void WebBrowser_Persist_Init(WebBrowser *This)
 {
     This->lpPersistStorageVtbl    = &PersistStorageVtbl;
+    This->lpPersistMemoryVtbl     = &PersistMemoryVtbl;
     This->lpPersistStreamInitVtbl = &PersistStreamInitVtbl;
 }
diff --git a/dlls/shdocvw/shdocvw.h b/dlls/shdocvw/shdocvw.h
index 28637bf0920..db47b637fc8 100644
--- a/dlls/shdocvw/shdocvw.h
+++ b/dlls/shdocvw/shdocvw.h
@@ -100,6 +100,7 @@ struct WebBrowser {
     const IOleInPlaceObjectVtbl         *lpOleInPlaceObjectVtbl;
     const IOleControlVtbl               *lpOleControlVtbl;
     const IPersistStorageVtbl           *lpPersistStorageVtbl;
+    const IPersistMemoryVtbl            *lpPersistMemoryVtbl;
     const IPersistStreamInitVtbl        *lpPersistStreamInitVtbl;
     const IProvideClassInfo2Vtbl        *lpProvideClassInfoVtbl;
     const IViewObject2Vtbl              *lpViewObjectVtbl;
@@ -152,6 +153,7 @@ struct InternetExplorer {
 #define INPLACEOBJ(x)   ((IOleInPlaceObject*)           &(x)->lpOleInPlaceObjectVtbl)
 #define CONTROL(x)      ((IOleControl*)                 &(x)->lpOleControlVtbl)
 #define PERSTORAGE(x)   ((IPersistStorage*)             &(x)->lpPersistStorageVtbl)
+#define PERMEMORY(x)    ((IPersistMemory*)              &(x)->lpPersistMemoryVtbl)
 #define PERSTRINIT(x)   ((IPersistStreamInit*)          &(x)->lpPersistStreamInitVtbl)
 #define CLASSINFO(x)    ((IProvideClassInfo2*)          &(x)->lpProvideClassInfoVtbl)
 #define CONPTCONT(x)    ((IConnectionPointContainer*)   &(x)->lpConnectionPointContainerVtbl)
diff --git a/dlls/shdocvw/webbrowser.c b/dlls/shdocvw/webbrowser.c
index c9af82f7448..49914f7184a 100644
--- a/dlls/shdocvw/webbrowser.c
+++ b/dlls/shdocvw/webbrowser.c
@@ -72,6 +72,9 @@ static HRESULT WINAPI WebBrowser_QueryInterface(IWebBrowser2 *iface, REFIID riid
     }else if(IsEqualGUID(&IID_IPersistStorage, riid)) {
         TRACE("(%p)->(IID_IPersistStorage %p)\n", This, ppv);
         *ppv = PERSTORAGE(This);
+    }else if(IsEqualGUID(&IID_IPersistMemory, riid)) {
+        TRACE("(%p)->(IID_IPersistStorage %p)\n", This, ppv);
+        *ppv = PERMEMORY(This);
     }else if(IsEqualGUID (&IID_IPersistStreamInit, riid)) {
         TRACE("(%p)->(IID_IPersistStreamInit %p)\n", This, ppv);
         *ppv = PERSTRINIT(This);