ForgeRock defines Major, Minor, and Maintenance product release levels. The release level is reflected in the version number. The release level tells you what sort of compatibility changes to expect.
Major (version: x.0.0)
Major releases bring big new features. Major releases can include changes even to stable interfaces. Major releases can drop previously deprecated functionality, and in rare cases drop evolving functionality that has not been explicitly deprecated. Major releases also include the changes present in previous Minor and Maintenance releases.
Minor (version: x.y.0)
Minor releases may include new features, backwards-compatible changes to stable interfaces in the same Major release, and incompatible changes to evolving interfaces. Minor releases can drop previously deprecated functionality. Minor release also include the changes present in Maintenance releases.
Maintenance (version: x.y.z)
Maintenance releases may include bug fixes and are intended to be fully compatible with previous versions from the same Minor release.