The author lost me. TL;DR; it depends on the contract. If you're paying for 9am-5pm and they're working on other projects during that time you've not approved, yes. If they're doing other work outside of work hours, it depends on the contract. If they're hourly/contractual and billing your for hours to work on projects you've not approved, yes. I've worked for companies, although stipulating a 9-5 work period stated that they owned all works created by me, unless otherwise cleared by legal (very common in finance). I had to ahead of time have clearance on any FOSS contributions by legal. It was a pain in the ass and net result was I didn't bother unless there was a critical isuse.