# $license->licenseKey()

- Source: `src/License.php#L70` <https://github.com/wagnerwagner/merx/blob/2.0.0-alpha.11/src/License.php#L70>

```php
$license->licenseKey(): null|string
```

## Return type

`null|string`

## Parent class

`Wagnerwagner\Merx\License`