Neighbor put up a fence against his boundary of an easement running the length
of our backyards. He rebuffed my offer to pay half since he weirdly thought I should put up another fence along my boundary to the easement (creating an alley). Right after he finished the fence I improved my yard across the easement as its an expired underground irrigation corridor. We put in about 2000 SQFT of lawn across the easement to his fence and technically added area to our .25 acre lot. I doubt the easement will ever be used for anything in the future since the utility relocated the irrigation into a pipe on our street (it was moved before we bought the house and before he put the fence in). Neighbor has since moved and I doubt the boundary will ever be contested.