Posted: 10/15/2009, Updated: 9/21/2010
In addition to using custom keywords to validate unformatted social security numbers (SSNs), Identity Finder also has the ability to invalidate false positives using custom negative keywords.
Negative keywords are words that, when they are found preceding a potential unformatted SSN result, are used to reject that potential SSN and ensure that it does not appear in the results.
For example, in a document containing 9 digit US Zip codes (without spaces or dashes - eg, 123456789) which has labels preceding each zip code such as, "Mailing Address" or, "Zip", or a state abbreviation such as, "NY", those keywords can be used to reject the unformatted 9 digit numbers and prevent them from appearing as valid SSN results. In the latter case, it may be desirable or necessary to add the complete list of state abbreviations to the list of negative keywords.
Similarly, if a file contains, "Tracking: 123456789" and 123456789 is a valid SSN, if Tracking is used as a negative keyword, then 123456789 would not appear as an SSN result.
There are two settings that enable and configure the custom negative keywords:
The UseNegativeKeywords setting must set to "Enable" (1), and then Identity Finder will use the keywords in the CustomNegativeKeywords list to invalidate potential SSNs. The is no UI in the client to configure these settings. They must be defined via policy, a configuration xml file, or directly in a system or user settings location.