The goal of this paper is to illustrate the use of category theory (CT) as a basis for the integration of manufacturing service databases. In this paper, we use as our reference prior work by Kulvatunyou et al. (2013, “An Analysis of OWL-Based Semantic Mediation Approaches to Enhance Manufacturing Service Capability Models,” Int. J. Comput. Integr. Manuf., 27 (9), pp. 803–823) on the use of web ontology language (OWL)-based semantic web tools to study the integration of different manufacturing service capability (MSC) databases using a generic-model approach that they propose in their paper. We approach the same task using a different set of tools, specifically CT and FQL, a functorial query language based on categorical mathematics. This work demonstrates the potential utility of category-theoretic information management tools and illustrates some advantages of categorical techniques for the integration and evolution of databases. We conclude by making the case that a category-theoretic approach can provide a more flexible and robust approach to integration of existing and evolving information.