This is the most common form of Interoperability. Company A makes a product and Company B makes a thing that works with that product, but doesn’t talk to Company A about it. Company A doesn’t know or care to know about Company B’s add-on.
Bibliography
Doctorow, Cory. 2019. “Interoperability: Fix the Internet, Not the Tech Companies.” Electronic Frontier Foundation. https://www.eff.org/deeplinks/2019/07/interoperability-fix-internet-not-tech-companies.