The notion of relative invariance is highlighted as a foundational principle in how corporate heritage identity traits can remain the same, yet change in meaning over time. Yet, little is published regarding how this notion manifests, or how corporate heritage stewards manage it in identity challenging situations. Utilizing a case study of one of the UK's oldest cancer charities, we highlight how two groups of protagonistsheritage defenders and service innovatorsshape the meaning of corporate heritage identity over time. We explore four core tensions that expose the multifaceted and complex nature of relative invariance and identify specific integration and compartmentalization strategies utilized to restore balance, allowing for the continued meaningfulness of corporate heritage identity. Overall, our study advances the notion of relative invariance, providing a more complete understanding of stewards' affinity toward corporate heritage and extending the field of corporate heritage identity into the nonprofit sector.