Searching for Personally Identifiable Information (PII)

This technical note discusses searching for and the redaction of documents containing personally identifiable information (PII).  

Why Search for PII?

Identifying PII reduces data privacy risks, data sharing exposure, and avoids implementation of high risk data discovery or recovery strategies during review.  

Common Types of Personally Identifiable Information (PII)

Credit card numbers   

Social Security Number (SSN)

Phone Number

Driver's license number 

Sensitive health information 

Importance of Removing PII from Documents not Legally Required

Some documents will contain both personally and non-personally identifiable information, some of which may not legally require redaction.  However, best practice is to remove PII from documents to reduce exposure or increased risk of data breach litigation.  

Examples would include:  

Email messages and attachments

Social media and blog posts (consumer and business)

Text messages and instant messages


Contextual data

Using the Lexbe eDiscovery Platform (LEP)To Search PII

Search Formats

The Search feature allows the use of wildcard "==", Boolean or a combination of keywords (SSN and Social Security Number) to locate PII inside documents. These pattern searches return results, even if the user does not include specific numbers. 

Social Security Number Search Options

Boolean option and wildcard "==" as a sequence of 09 digits:

Wildcard "=== == ====" (w/spaces)

Wildcard "=========" (w/o spaces)

Wildcard "===-==-====" (w/dashes)

Search "SSN" 

Search "Social Security Number"

The example below illustrates the search results using the wildcard "=="  and Boolean options (“279-52-0083”, “279 52 0083”, and “279520083”).  The URL right argument is automatically constructed in LEP:

The user may also try to search using an advanced Boolean format, for example the keyword Social, AND connector, and the last four digits of a social security number (Social AND **0083).

Credit Card Numbers Search Options

Boolean option and wildcard "==" as a sequence of 16 or more digits as follows:

Wildcard "==== ==== ==== ====" (w/spaces)

Wildcard "================"  (w/o spaces)

Wildcard "====-====-====-====" (w/dashes)

Search "Credit Card"

Phone Numbers Search Options

Wildcard "=== === ====" (w/spaces)

Wildcard "==========" "  (w/o spaces)

Wildcard "===-===-====" (w/dashes)

Search "Phone Number" 

The same option can be used for the international phone number format, using wildcard "==" to match the number of digits.  For example, the number 011 44 20 8384 6454 may be searched with wildcard "==" as follows:

Wildcard "=== == == ==== ====" (w/spaces)

Wildcard "==============="   (w/o spaces)

Wildcard "===-==-==-====-====" (w/dashes)

Searches are not perfect.  OCR errors or format differences may cause items to be missed.  Search returns may be over-inclusive in connection with a search for SSN, credit card or phone numbers.  These require manual review.

Save and Share Searches

Every search is automatically saved.  The user may pin and share searches, delete existing records or Cancel.

Shared. View shared searches.  To share or unshare searches, click the Edit button.  Check or uncheck the Shared icon checkbox when the Shared/Pinned Searches dialog box appears.  This shares searches with users that have access to the case.

Pinned. Click on the Edit hyperlink, select search by the title, use the check-box to pin searches. Click OK to save changes or Cancel.  The selected search will be moved to the Pinned section. 

Recent. The screen displays the five most recent searches. Click the Edit hyperlink for a full list of searches.

PII Search Spreadsheet Template

Attached to this technical note is a template entitled PII Search Links Template vers 2015-03.xlsx.  Download the spreadsheet to search PII data (up to 1,000 search terms are supported in the template). Document sets containing search results may be mass tagged to Responsive and/or Privilege with Multi Doc Edit.  Documents opened in the Document Viewer from search results are highlighted in the Hits and Text tabs.  

Develop a Workflow to Manage Document Review with Redaction of PII

See Redaction for more information.  

Prepare Custom Fields for Redaction Tagging

This step is needed only if specific issue-tagging will be done at the time of the responsiveness review (e.g. documents to be redacted). From the Management->Manage Custom Doc Fields page, create a custom coding section/field to tag files for redaction. For example, Coding Section Redaction and then Coding Field (check-box) Files TBR.

Only Admin users can create custom fields for any purpose.

Search for Documents Including PII

From the Search page, use the wildcard "==", Boolean or combine keywords to identify documents containing PII.

Filter Documents to be Redacted

Go to the Browse page, apply filters under the custom coding section/field recently created, and use Multi-Doc Edit to tag all the documents with the custom coding section/field. 

Apply Redaction

The user may redact documents directly in LEP or upload documents that have been redacted outside of LEP. 

Review Documents for Responsiveness


Responsive documents are those which are required by a Request for Production.