So it must an increase in reserves play because your calculation isn't value it's really your estimates of the total profits generated on 26.8 % of the net oil produced over the entire life of the field. Who is going to pay $ 375 million in advance ? Where's the return to them, it would be just a dollar trading exercise !!  The only way for an acquirer to make a profit after buying out SNM for that amount , your estimated value, is if the field is considerably larger than 500 mmbbl or the profit is much greater than the $ 375 Million or they pay considerably less than $ 375 Million. In any event General were quite happy with $ 600 Mill which is the equivalent of $ 302 Mill to SNM, the best benchmark to date . 

I'm certain the Lundins have every intention of getting as much money as they possibly can for each share of everything they own but that doesn't mean they are married to any one play in perpetuity. Taqa bought most of the dog starting at the head end, they are now the operator and that normally commands a premium price. SNM just owns the wagging bit and that part may not attract an equivalent price. Selling and moving on to something they control might be a better long term option.

Watching with great interest and thanks for your input.