Trademark Dispute — employer claiming my side project IP

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Illustrative scenario prepared by my practice.
For informational purposes only. This is not legal advice. Laws vary by jurisdiction. Consult a qualified attorney for advice specific to your situation.
Hypothetical question

Has anyone dealt with something like this? I'm not sure what my options are.

employer claiming my side project IP. I've been dealing with this for about 14 weeks now and the situation isn't improving.

This involves content I created over the past 14 months. I do have documentation proving my ownership and timeline.

Do I have a strong case? What should my next steps be?

Illustrative response

The statute of limitations for copyright is 3 years. Don't wait too long.

Illustrative response

Copyright registration isn't required but it helps a lot with damages.