Users who do not know there Mathcad product code can refer below steps on how to get the Product Code:
Product Code consists of 22 alphanumeric characters in length. General format of product code is xxxxxxxxxxxxxxx - xxxx – xxxx
Effective April, 1st 2015 - PTC no longer supports Mathcad releases 11, 12 and 13 . There was a communication on this change. For more details refer more information refer - http://support.ptc.com/WCMS/files/164017/en/PTC_Mathcad_Support_Announcement.docx.
I hope the above details help.