Do trademarks diminish the substitutability of products in innovative knowledge-intensive services?

Trademarks are often supposed to reduce substitutability and imitability of product innovations. Using German CIS data for 2010, we provide empirical evidence that trademarking firms assess easy product substitutability as less characteristic for their competitive environment. This is particularly the case for knowledge-intensive service providers, product innovators and firms which consider trademarks as important intellectual property rights. This suggests that trademarks are an important supplementary mechanism to protect innovations in knowledgeintensive services.