[CONNECT .NET, C++] ItemTypeLibrary Create (string name, DgnFile dgnfile, bool forCopy)

public static ItemTypeLibrary Create (
  string name,
  DgnFile dgnfile,
  bool forCopy);

What is the purpose of the final argument forCopy in that method declaration?  There's a similar method in the C++ class, with a similar absence of explanation in the help doc.