Sensitive information type limits

These limits apply to all Microsoft Purview policies that use SITs.

To ensure high performance and lower latency, there are limitations in custom SIT configurations, as described in the following table.

Limit	Value
Maximum number of custom SITs created through the Microsoft Purview compliance portal	500
Maximum length of regular expression	1024 characters
Maximum length for a given term in a keyword list	50 characters
Maximum number of terms in keyword list	2048
Maximum number of distinct regexes per SIT	20
Maximum size of a keyword dictionary (post compression)	1MB (~1,000,000 characters)
Maximum number of keyword dictionary based SITs in a tenant	50

Note

If you have a business need to create more than 500 custom SITs, please raise a support ticket.

Instance count supported values for SIT

The SIT instance count limit applies when using SITs in these solutions:

• Microsoft Purview Data Loss Prevention policies
• Microsoft Purview Information Protection policies
• Microsoft Purview Data Lifecycle Management
• Communication Compliance
• Microsoft Purview Records Management
• Microsoft Defender for Cloud Apps
• Microsoft Priva

For a scanned item to satisfy the rule criteria, the number of unique instances of a SIT in any single item must fall between the min and max values. This is called the Instance count.

• Min field: the lower limit (minimum number) of unique instances of a SIT that must be found in an item to trigger a match. The min field supports values of 1 to 500.
• Max field: the upper limit on the number of unique instances of a SIT that can be found in an item and still trigger a match. The max field supports the following values:
  • 1 to 500 - Use a value between 1 and 500 when you want to set a specific upper limit of 500 or less on the number of instances of a SIT in an item.
  • Any - Use Any when you want to ensure that the unique instance count criterion is satisfied when an undefined number of unique instances of a SIT are found in a scanned item and that the specified number of unique instances meets or exceeds the minimum number of unique instances value. In other words, the unique instance count criteria are met as long as the min value is met.

For example, if you want the rule to trigger a match when at least 500 unique instances of a SIT are found in a single item, set the min value to 500 and the max value to Any.