> ## Documentation Index
> Fetch the complete documentation index at: https://base-a060aa97-docs-add-b20-spec.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# IPolicyRegistry.policyExists

> Generated B20 reference for policyExists(uint64).

[Related concept](/base-chain/specs/upgrades/beryl/b20/specification/concepts/policies-and-scopes)

## Signature

```solidity theme={null}
function policyExists(uint64 policyId) external view returns (bool);
```

| Field               | Value                  |
| ------------------- | ---------------------- |
| Selector            | `0x330f5637`           |
| Canonical signature | `policyExists(uint64)` |

## Description

Returns whether `policyId` is a built-in sentinel or a previously-assigned custom ID. Never reverts.
Param: policyId Policy to query.
Return: Whether the policy exists.

## Access control

Read-only or ERC-20-standard access rules unless the NatSpec states otherwise.

## Policy interaction

This is part of the singleton PolicyRegistry surface used by B20 policy scopes.

## Example

```solidity theme={null}
IPolicyRegistry(target).policyExists(arg0);
```

## Related

* [IPolicyRegistry reference](/base-chain/specs/upgrades/beryl/b20/specification/reference/interfaces/IPolicyRegistry)
* [Constants & addresses](/base-chain/specs/upgrades/beryl/b20/specification/reference/constants-and-addresses)