An administrator can bulk delete sign up requests in the Connector. 
  1. In the Connector, Click Sign Up Requests
  2. Select all the records that should be deleted
  3. Click Delete Selected
  4. In the Pop Up: Are you sure you wish to delete the selected transaction(s)?, click Yes

Please note, the Requests are created because the Connector does not identify an existing Raiser's Edge record that matches, so one can be created through a Sign Up Request. 

Once this request is deleted, it will not be sent over again, unless the Sphere profile has been updated.  In general, we do not recommend deleting sign up requests, unless the administrator does not want a Raiser's Edge constituent record.