Well, I'm sure the laws and case law varies from state to state, and I'm definitely not familiar with Oklahoma. It's pretty vague in Texas, as a matter of fact, and we're known for having a pretty tight property code. So it's a tricky area. Access easements are much different than utilities easements here, and there's definitely such a thing as an "implied" access easement that's legally binding even without any such agreement recorded in the property records.
I obviously can't give you legal advice, but I bet your attorney will want to counter sue. I would be shocked if their restraining order weren't granted, but don't look at that as a sign of impending defeat. It would mean little. At worst, both sides have a reasonable argument and the attorneys will work something out before trial. At best, the case is dismissed and the judge orders your neighbors to move off your land. Does their property have access to a road? The judge would be reluctant to land lock them, probably, especially since they've been there so long.
It sounds like an interesting case. Keep us posted if you don't mind.
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