Advice from HN: I'm about to be fired because I declared prior IP months ago.

I would suggest that you put together a moderately short memorandum of the facts. You will need a time line, dates and names of attendees of meetings, summaries of what happened at each meeting and what happened. If you keep an appointments diary, copy out the relevant pages. Collect copies of all the employment documents. This will save time and money if you need to go forward. In the future, when you have a meeting with anyone involving this, write a memorandum to the file recounting exactly what happened with quotations, agreements, action items, etc. Keep everything factual and avoid editorial content and presumptions of intent.

Check your employment and intellectual property agreements. I suspect that your employer does not have approval rights on your excluded intellectual property declaration. The purpose of that declaration is to make the company's job simpler--they claim to own everything you did not exclude--and since it describes your intellectual property prior to the point of employment, they have no say in its content, you own what you own. I can imagine a situation where the company might ask for a clarification of what you are excluding, but they really have no right to challenge the substance. Moreover, I further suspect that the fact that they did not come back to you in a timely fashion and that they went ahead and employed you immediately would be interpreted as _ipso facto_ agreement that the declaration was an adequate description of your excluded intellectual property.