In order to make it rain in the target area, you must generally seed in the area adjacent to the target area about 30 minutes before the clouds get to the target area. Permission must be obtained from the State of New Mexico to do that. Obviously, we can fly in New Mexico without their permission, but we can t seed without their permission. As a rule, however, the regulatory authorities in New Mexico, Oklahoma, and Kansas are very cooperative. Those data are available if you are interested.
Common sense says yes.
Reality, however, is not so clear. Rain does not travel in a straight line. Research indicates that areas directly contiguous to seeding operational areas actually see increased rainfall, but further away, results haven t been determined. Anyone can sue. That means you are entitled to all the moisture above you and if you can get it, your neighbor is out of luck.