# not in

### Description

`not in` is used to check if a value is present in a list or a [taxonomy](/guides/glossary/taxonomy.md). If it is **not**, the expression evaluates to true.

On the left side of `in`, there is always a single value. The list of options, which could be a taxonomy, goes on the right side of `in`.

### Example

If a [document](/guides/glossary/document.md) is only relevant to companies who are not registered in the European Union, you could attach this condition to it:

```
e is Entity
e.domicile not in EUCountries
```

There is one answer for what the domicile of an entity is, so this is a single value. With the conditions in the example, you check whether this value is **not** a part of the taxonomy `EUCountries`, which predictably consists of a list of all the member states of the European Union.

If `e.domicile` is in the United Kingdom, the condition evaluates to true. The document will be included in the [case](/guides/glossary/case.md). If `e.domicile` is Belgium, the condition evaluates to false, meaning the document is excluded.


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