If you already own a licensed copy and need to move it to a new machine, your first step should be checking your official account history.
: If the software is still installed on an old PC, you might find evidence of activation in the Windows Registry under HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\Adobe Acrobat\11.0\Activation . 2. The Risks of "Serial Number Top" Searches
: Search your inbox for "Adobe Order" or "Serial Number" from the time of your original purchase (likely between 2012 and 2015).