When you receive a notification to add a contact, you have the opportunity to add, ignore or block the person. If you choose to block them, you are presented with an additional option to report the blocked user to Skype.
The instructions for blocking and reporting vary according to the version of Skype you are using. Select one of the following:
The Skype Name of the blocked person is stored by us once they are reported for abuse, but the content, such as IM messages or the contact request itself, is not.