The License Registry stores all license-related states within the protocol, including managing global state like registering new License Templates like the Programmable IP License (PIL💊), attaching licenses to individual IP Assets, registering derivatives, and the like:

LicenseRegistry.sol
/// @dev Storage of the LicenseRegistry
/// @param defaultLicenseTemplate The default license template address
/// @param defaultLicenseTermsId The default license terms ID
/// @param registeredLicenseTemplates Registered license templates
/// @param registeredRoyaltyPolicies Registered royalty policies
/// @param registeredCurrencyTokens Registered currency tokens
/// @param parentIps Mapping of parent IPs to derivative IPs
/// @param parentLicenseTerms Mapping of parent IPs to license terms used to link to derivative IPs
/// @param childIps Mapping of derivative IPs to parent IPs
/// @param attachedLicenseTerms Mapping of attached license terms to IP IDs
/// @param licenseTemplates Mapping of license templates to IP IDs
/// @param expireTimes Mapping of IP IDs to expire times
/// @param licensingConfigs Mapping of minting license configs to a licenseTerms of an IP
/// @dev Storage structure for the LicenseRegistry
/// @custom:storage-location erc7201:story-protocol.LicenseRegistry
struct LicenseRegistryStorage {
  address defaultLicenseTemplate;
  uint256 defaultLicenseTermsId;
  mapping(address licenseTemplate => bool isRegistered) registeredLicenseTemplates;
  mapping(address childIpId => EnumerableSet.AddressSet parentIpIds) parentIps;
  mapping(address childIpId => mapping(address parentIpId => uint256 licenseTermsId)) parentLicenseTerms;
  mapping(address parentIpId => EnumerableSet.AddressSet childIpIds) childIps;
  mapping(address ipId => EnumerableSet.UintSet licenseTermsIds) attachedLicenseTerms;
  mapping(address ipId => address licenseTemplate) licenseTemplates;
  mapping(bytes32 ipLicenseHash => Licensing.LicensingConfig licensingConfig) licensingConfigs;
}

Notable Functions

LicenseRegistry.sol
function attachLicenseTermsToIp(address ipId, address licenseTemplate, uint256 licenseTermsId) external onlyLicensingModule

This function allows you to attach License Terms to an IP Asset.

LicenseRegistry.sol
function registerDerivativeIp(address childIpId, address[] calldata parentIpIds, address licenseTemplate, uint256[] calldata licenseTermsIds, bool isUsingLicenseToken) external onlyLicensingModule

This function allows you to register an IP Asset as a derivative of another IP Asset, unlocking things like claimable royalty flows from the 💸 Royalty Module.