Comment Re:Turn the Screws on Their Thumbs (Score 2, Informative) 542
Well, you can just write them a polite email informing that you use the domain and it is not up for sale. However if they really need the domain, and are willing to recompensate you for the hassle of moving to another domain, you would be willing to help them out.
That way they can make an offer, are you get into no legal trouble (You clearly show that you do not wish to sell the domain, unless it is to help them out).