> [!CAUTION]
> **Caution:** This documentation is for Google Ads API **v23** . The latest active version is [**v26**](https://developers.google.com/google-ads/api/reference/rpc/latest/UserListRuleInfo).

A client defined rule based on custom parameters sent by web sites or uploaded by the advertiser.

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v23/common/user_lists.proto)

| Fields ||
|---|---|
| ## `rule_item_groups[]` | `UserListRuleItemGroupInfo` List of rule item groups that defines this rule. Rule item groups are grouped together based on rule_type. |
| ## `rule_type` | `UserListRuleType` Rule type is used to determine how to group rule items. The default is OR of ANDs (disjunctive normal form). That is, rule items will be ANDed together within rule item groups and the groups themselves will be ORed together. OR of ANDs is the only supported type for FlexibleRuleUserList. |