The GetClipboardOwner function retrieves the window handle of the current owner of the clipboard.
HWND GetClipboardOwner(VOID)
This function has no parameters.
If the function succeeds, the return value is the handle of the window that owns the clipboard.
If the clipboard is not owned, the return value is NULL. To get extended error information, call GetLastError.
The clipboard can still contain data even if the clipboard is not currently owned.
In general, the clipboard owner is the window that last placed data in clipboard. The EmptyClipboard function assigns clipboard ownership.