Ebby, you’ve gotten a lot of good advice. All of this is probably confusing but I think you are on the right track to get it sorted out.
On your point about the lease your father signed with Marathon in 2010, although it stated it was for only a three-year term, because a well was drilled and was producing before the end of that initial three years, the term of that lease was extended and became “held by production”, meaning the term of the lease automatically continues for as long as that first well, or later wells drilled in a unit that includes that leased acreage, continue to produce.
Legacy did take over as operator from Marathon so on your father’s lease and any other leases Marathon held in that unit, and after 2015 became the Lessee. It’s not worth looking for but a formal assignment from Marathon to Legacy that lists all those leases was probably recorded in the Shelby County deed records in 2015. The main point is, the terms of that original 2010 lease still apply to the mineral interest you inherited from your father. They will continue to be important and remain in effect as long as production continues there.
It doesn’t matter now, but you mentioned your father’s lease you found in the deed records was in the amount of $10. That probably doesn’t mean the actual lease bonus amount he was paid by Marathon was only $10. Documents covering leases, sale prices, and lots of other things are often stated that way (usually as, “ten dollars and other valuable consideration”) in documents that will be recorded and open for public view. In other words, Marathon didn’t want to let the general public know specifically what they paid your father so they just said the amount was $10.
On your question about things you should be aware of on the transfer documents you’ve gotten from Revenir…one question is, do you have the information you need to confirm the share of the producing unit your father held, which Revenir should now be placing in your name? In your first post you talked about your father receiving a first check from Legacy for $110.98. You didn’t indicate what period of time that check covered. It could have been based on one month of production from one well, or an accumulation of royalty amounts over a period of time from multiple wells. Later you said the lease your father signed with Marathon covered 80.3384 acres. But that doesn’t indicate whether your father owned the full mineral interest in that 80+ acre tract or some fraction of the total interest. Just a guess, but based on the amount of that payment I think your father may have owned a small partial interest in that 80 acres. A statement should have come with that first check that showed the period of time (production month or months) that royalty payment covered, the wells it covered, which are normally listed separately in a pooled unit, and your father’s decimal ownership interest that the royalty payment was calculated on. If you can’t figure out each of those factors from the statement, or you don’t understand how your father’s decimal interest was calculated, I think it would be logical to contact Revenir’s Owner Relations department asking for an explanation of those points.
It looks like the two wells drilled by Legacy didn’t start producing until earlier this year, so they may relate to that first check your father received, but the original well drilled by Marathon has apparently been producing since 2011 or 12. It seems like your father should have already been receiving royalty payments related to that earlier well. After 2015 those payments would have come from Legacy since they took over as the operator. If you know he didn’t receive any previous royalty payments you could also ask Revenir about that, and like J_Walker suggested above check the State’s unclaimed fund site in your father and grandfather’s names.
The information fttxguy gave you about the wells in the original 674-acre unit Marathon formed becoming part of a 22,000-acre Cothrom A unit, is something I know nothing about. I’d seen the well name changes in RRC’s records but wasn’t aware of that larger unit, or how it might apply to your interest.