diff --git a/include/qpdf/QPDF.hh b/include/qpdf/QPDF.hh
index 45b9fee..9774ca1 100644
--- a/include/qpdf/QPDF.hh
+++ b/include/qpdf/QPDF.hh
@@ -790,7 +790,6 @@ class QPDF
     // End of the public API. The following classes and methods are for qpdf internal use only.
 
     class Doc;
-    class StreamCopier;
 
     inline bool reconstructed_xref() const;
     inline Doc& doc();
diff --git a/libqpdf/QPDFObjectHandle.cc b/libqpdf/QPDFObjectHandle.cc
index 0b40d5b..20933a3 100644
--- a/libqpdf/QPDFObjectHandle.cc
+++ b/libqpdf/QPDFObjectHandle.cc
@@ -1949,7 +1949,7 @@ QPDFObjectHandle::copyStream()
             dict.replaceKey(iter.first, iter.second.shallowCopy());
         }
     }
-    QPDF::StreamCopier::copyStreamData(getOwningQPDF(), result, *this);
+    QPDF::Doc::StreamCopier::copyStreamData(getOwningQPDF(), result, *this);
     return result;
 }
 
diff --git a/libqpdf/qpdf/QPDF_private.hh b/libqpdf/qpdf/QPDF_private.hh
index 752f686..06157de 100644
--- a/libqpdf/qpdf/QPDF_private.hh
+++ b/libqpdf/qpdf/QPDF_private.hh
@@ -13,19 +13,6 @@
 
 using namespace qpdf;
 
-// StreamCopier class is restricted to QPDFObjectHandle so it can copy stream data.
-class QPDF::StreamCopier
-{
-    friend class QPDFObjectHandle;
-
-  private:
-    static void
-    copyStreamData(QPDF* qpdf, QPDFObjectHandle const& dest, QPDFObjectHandle const& src)
-    {
-        qpdf->copyStreamData(dest, src);
-    }
-};
-
 class QPDF::ObjCache
 {
   public:
@@ -347,9 +334,23 @@ class QPDF::Doc
     class JobSetter;
     class ParseGuard;
     class Resolver;
+    class StreamCopier;
     class Streams;
     class Writer;
 
+    // StreamCopier class is restricted to QPDFObjectHandle so it can copy stream data.
+    class StreamCopier
+    {
+        friend class QPDFObjectHandle;
+
+      private:
+        static void
+        copyStreamData(QPDF* qpdf, QPDFObjectHandle const& dest, QPDFObjectHandle const& src)
+        {
+            qpdf->copyStreamData(dest, src);
+        }
+    };
+
     Doc() = delete;
     Doc(Doc const&) = delete;
     Doc(Doc&&) = delete;