Worked on the opengeospatial/ontology-crs repository to clarify disjointness relationships within the Coordinate Reference System ontology, enhancing semantic clarity and logical consistency. The approach involved ontology engineering techniques to define explicit disjointness between classes such as VerticalCoordinateSystem and OrdinalCoordinateSystem, as well as Datum and CRS, with updates reflected in alignment.csv. Leveraged skills in the Semantic Web and CSV data management to ensure that these changes support more reliable reasoning and interoperability across geospatial datasets and tools. Maintained commit-level traceability and thorough documentation, enabling reproducible semantic changes and facilitating downstream validation in alignment with geospatial standards.