US Airways, McKesson, City of Houston, Automatic Data Processing (ADP), AlliedBarton Security Services

Under Review: 
No Review
Date Breach Made Public: 
July 30, 2013
Tempe , AZ
United States
Records Breached: 


Breach Total Number: 
4 500
Year of Breach: 
Type of organization: 
Type of breach: 

A programming error at ADP resulted in the exposure of employee names, Social Security numbers, and other information on W-2 forms.  Employees could have inadvertently downloaded the W-2s of other employees.  The error was corrected on May 4 and involved W-2 forms for tax years 2010, 2011, and/or 2012. ADP alerted US Airways to the issue on June 6, 2013.

UPDATE (09/13/2013): McKesson and the city of Houston were also affected by the breach.

UPDATE (09/30/2013): AlliedBarton Security Services was also affected.  It appears that 206 ADP customers were affected.  Two of the customers affected have at least 4,500 employees.