diff --git a/gfx/layers/d3d10/CanvasLayerD3D10.cpp b/gfx/layers/d3d10/CanvasLayerD3D10.cpp
index b484df4389ca..d580889fc070 100644
--- a/gfx/layers/d3d10/CanvasLayerD3D10.cpp
+++ b/gfx/layers/d3d10/CanvasLayerD3D10.cpp
@@ -93,6 +93,8 @@ CanvasLayerD3D10::Initialize(const Data& aData)
       // XXX for ANGLE, it's already the right-way up.  If we start using NV GL-D3D interop
       // however, we'll need to do the right thing.
       mNeedsYFlip = PR_FALSE;
+      mHasAlpha =
+        mSurface->GetContentType() == gfxASurface::CONTENT_COLOR_ALPHA;
     }
   }
 
@@ -239,7 +241,7 @@ CanvasLayerD3D10::RenderLayer()
   ID3D10EffectTechnique *technique;
 
   if (mDataIsPremultiplied) {
-    if (mSurface && mSurface->GetContentType() == gfxASurface::CONTENT_COLOR) {
+    if (!mHasAlpha) {
       if (mFilter == gfxPattern::FILTER_NEAREST) {
         technique = effect()->GetTechniqueByName("RenderRGBLayerPremulPoint");
       } else {
diff --git a/gfx/layers/d3d10/CanvasLayerD3D10.h b/gfx/layers/d3d10/CanvasLayerD3D10.h
index 426119a72e88..6df080a4a25f 100644
--- a/gfx/layers/d3d10/CanvasLayerD3D10.h
+++ b/gfx/layers/d3d10/CanvasLayerD3D10.h
@@ -51,10 +51,11 @@ class THEBES_API CanvasLayerD3D10 : public CanvasLayer,
 {
 public:
   CanvasLayerD3D10(LayerManagerD3D10 *aManager)
-    : CanvasLayer(aManager, NULL),
-      LayerD3D10(aManager),
-      mDataIsPremultiplied(PR_FALSE),
-      mNeedsYFlip(PR_FALSE)
+    : CanvasLayer(aManager, NULL)
+    , LayerD3D10(aManager)
+    , mDataIsPremultiplied(PR_FALSE)
+    , mNeedsYFlip(PR_FALSE)
+    , mHasAlpha(PR_TRUE)
   {
       mImplData = static_cast<LayerD3D10*>(this);
   }
@@ -83,6 +84,7 @@ private:
   PRPackedBool mNeedsYFlip;
   PRPackedBool mIsD2DTexture;
   PRPackedBool mUsingSharedTexture;
+  PRPackedBool mHasAlpha;
 };
 
 } /* layers */