In another online retailer I have found the following comment on the usability of the Mouse:
The mouse works only in conjunction with a Wacom Intuos tablet !!!! - So no serial number indicated.
On the American and English website Wacom is under [...] clearly stated compatibility: Five Button Mouse; Part number: KC100 - This device works with Intuos5 and Intuos4 pen tablets only. It will not work with the Intuos3, Intuos2, Intuos and tablets.