I have recieved a cease and desist order from a past employer. At the time I left I communicated that I was gong to work for a like business. They acknowledged that several of my clients would follow me and even released one from a contract to allow them to do so and provided myself and the client with a release. Now they are struggling and they have sent me a letter to cease working with any and all clients, accusing of taking trade secrets (?) saying that I am hurting thier business as my sales materials too closely resemble theirs. They are also cllaiming that I misrepresented to a new client of mine that I was still in there employ. I was in their employ when I met this client. I have my own logo, business cards and other items that do not come close to theirs. They claim that my proposals are the same and they may be close as I wrote both. I do not have a non-compete. But they want all my back wages from when I gave notice. Can they do this and do they have a case?
If there's no non compete agreement in place they more or less cannot tell you what to do with what you carried out inside your head. I suspect what you got was a nastygram from somebody in the company. You owe them nothing. However they may sue you. I suggest you hire an attorney to tell them that they've got no basis for their demands. Things go better with lawyers.