Piwik\Plugins\Marketplace\LicenseKey::set PHP Method

    public function set($licenseKey)
    {
        if (!isset($licenseKey) || $licenseKey === false) {
            $this->delete();
        } else {
            Option::set('marketplace_license_key', (string) $licenseKey);
        }
    }

 private function setLicenseKey($licenseKey)
 {
     $key = new LicenseKey();
     $key->set($licenseKey);
     $this->marketplaceClient->clearAllCacheEntries();
     $this->expired->clearCache();
 }