Use is Open. Validity is Conditional. Core Statement Use of OOF® standards is open. Validity within the OOF® system is conditional. This principle defines the difference between access and system recognition. Anyone may use OOF® methodologies. Only systems that satisfy defined structural conditions may be considered valid within the OOF® framework. Open Use Anyone may: read OOF® standards use their concepts implement their logic Use is open and unrestricted. Open access enables adoption, experimentation, learning, and implementation across environments. System States A system may exist in one of the following states: Open Use — the system uses OOF® concepts without structural validation Compatible — the system aligns with defined methodological conditions Validated — the system satisfies full validation and enforcement conditions These states are fixed and non-interchangeable. Use alone does not create compatibility. Compatibility alone does not create validation. Recognition and Reference Use of OOF® standards does not require permission. However, recognition within the OOF® system requires clear reference to the canonical source. Without valid reference: use may still occur but the system is not OOF®-recognized and cannot claim compatibility or validated status within the framework Reference supports: traceability transparency alignment with canonical meaning What Open Use Does Not Grant system validity compatibility status validated status methodological recognition within OOF® Use alone does not create validity. Validity Condition A system is valid within OOF® only if: structural conditions are satisfied defined rules are respected system behavior aligns with methodology If these conditions are not met: the system is considered non-valid within the framework its outputs are not recognized as valid within OOF® System Principle Use is open. Validity is conditional. Recognition requires reference. Relationship to OOF® Protection This principle operates within the broader OOF® protection and compatibility framework. Open access preserves adoption. Conditional validity preserves system integrity. Final Statement Use is open. Validity is conditional.