Disagreement over how much IP to put in paper
You are probably just stuck. &quot;Trade Secret&quot; is a valid concern of any profit making organization. And the fact that what you have done isn't patentable now doesn't mean that it can't later be combined with other things to result in products and patents in the future. Large organizations hold quite a bit of IP in reserve hoping for future breakthroughs. And even if the company can't think of a way to exploit the work, they would hesitate to provide a boost to any competitor.
So, your manager is probably telling you true. Your employment contract probably says something about that.