So given sufficient foresight, the prospect of a 1980 punishment hurts the 1950 owners, even if they sell in the interim.
1950 owners may be punished in 1980.
mnli hypothesis: 1950 owners may be punished in 1980. premise: So given sufficient foresight, the prospect of a 1980 punishment hurts the 1950 owners, even if they sell in the interim.