I am a software engineer. While I was working for a previous employer I built a software system from scratch. Part of my employment agreement was anything made for that employer on company time or using company resources belonged to them. Approximately 6 months ago I left that position and took a position with a different company.
A few months ago I realized that several of the technologies and techniques I have learned while working with the new company could be applied to that system to make it much better. I have been thinking about rebuilding a similar system on my own and trying to sell it. As far as I am aware there are no patents or anything like that on any parts of the system.
Given that the new system will be very similar to the first system I built, and utilize many of the techniques I figured out while building the first system, will my former employer have any rights to the new system if it’s built entirely with my own personal resources?