Can I say which companies use my open source software?
<p>I have written some open source (MIT License) software. I wrote the software for my own company <strong>Company A</strong>, that is legally registered with myself as the only employee. I only registered it so I could contract between jobs.</p>

<p>Recently I began a new full-time job in a senior position <strong>Company B</strong>, and we build software, as an agency, for some very large global companies <strong>Company X</strong>.</p>

<p>If I build software in <strong>Company B</strong> and use some of the open source libraries I built in <strong>Company A</strong>, can <strong>Company A</strong> say the open source software is used by <strong>Company X</strong>?</p>

<p>Essentially I want to create a public web page about the open source software, and I want to know if I can say it's used by <strong>Company X</strong>?</p>

<p>or something like: used in <strong>Company X</strong>'s <strong>Product X</strong>?</p>

<p>If I understand correctly, you know that X is using your software thanks to your inside knowledge as an employee of B. As a rule it is not permitted for you to reveal this information because it is owned by B.</p>

<p>Its also a little tendentious to claim that X is using your software, since it is only doing so as a result of its incorporation by B. It would be more accurate to say that B is using your software.</p>

open-source-software