In the situation (1) a UMO may be pooled, but not share in the proceeds, as to compensation for producing his presumed share of his drained assets. Further his recourse is to drill his own well, but being already pooled into an existing unit, his permit will be denied.
In the situation that (2) the UMO tract is a drillsite tract, the State has granted statutory forfeiture of ownership of subsurface assets, though he is pooled, and not leased.
Either way, given that all E&P companies are in business to profit, the best strategy is to stike minimal lease terms with widow's legacy tracts, pool others, and kiss off the legal rights of the others.....hmmm.