CAM - Equipment Master data changed automatically

Hi

All of a sudden the responsible business unit and serial numbers of all the equipments have been changed in equipment master. What might be the reason for this ? What has cased this either any update has been run by the end user or any batch application which does this ?

Note:- End users are having only limited access to the applications.

Kindly advise the steps to be taken in order to avoid repetition of same problem in future. Also is there any way revert back the changes other than backup or SQL or manual way.

Thanks & Regards,

Nadir