I mean if someone makes you an offer and you say it's worth x amount and that person accepts the offer at that price. Sounds like a verbal contract to me. If it wasn't a serious price than he should have not laid out any price at all and said "NOT FOR SALE" to the offer-er. Instead this passive aggressive moronic nerd decides to put a PRICE on the domain not once but 3 times (50k, 100k, 200k). The fool is getting sued now and will have to pay legal fees to defend himself. Oh how he could've avoided that by not being passive aggressive and being straightforward.
The price of being a fool.
It'll be interesting to see if Jump gets anywhere with it. Not that I'm rooting for anyone in this case. Only pointing out that don't be stupid when it comes to offers being thrown at you for an asset. If you do not intend to sell, do not be ambiguous and do not accept any offers, just say no.