There have been a lot of cases on conservation easements of late. My impression is that planners may well have gotten just a little carried away with the concept. You get a tax deduction for giving away a “might have been”, a fable in a way and the more fantastic the fable the greater the tax deduction. The way it works is that you have a piece of property that, hypothetically, could be developed, but there is a bunch of do-gooders or city or regional planners who would like to see it stay the way it is because it looks nice to drive by or is a refuge for birds or, in the big city, preserves the historic character of the neighborhood. So you give up the right to change the property, which is worth something, probably. For that you get a charitable deduction.