[PaulDavisThe1st]

The airspace is not owned by the land owner, certainly not above a relatively low height. Since the rain originates outside the owner-controlled slice of airspace, there's an argument that they do not have the right to control it.

[dredmorbius]

There's an interesting (and in my view very poorly grounded in factual basis) common law (caselaw) doctrine called Rule of Capture which applies in at least some jurisdictions concerning various "wild and migratory" resources, including both wild animals and mineral resources, with notable case history involving both groundwater (see Pecos County Water District #1 vs Clayton Williams et al (1954), concerning Stockton, TX) and petroleum and natural gas.

<https://en.wikipedia.org/wiki/Rule_of_capture>

I'd written up the Stockton, TX, case at Reddit: <https://old.reddit.com/r/dredmorbius/comments/5w1zw3/rule_of...>

I'd submitted an article some years back that's one of the few I've found even discussing the principle:

<https://www.texasobserver.org/playing-by-the-rule/>

<https://news.ycombinator.com/item?id=18005310>

What's fascinating to me are a few elements of this rule:

- It's effectively an argument from ignorance, with a key element being that the behaviours of these resources is not and cannot be known. Increasingly, both premises are now false, but significant case law still stands. One specific being a Texas Supreme Court ruling, Houston & Texas Central Railroad Co. v. East (1904). I've been unable to acquire a copy of this and would very much like to do so.

- The principle has exceedingly interesting implications over just what "property" is, and where property rights emerge. Given the centrality of this principle to virtually our entire present economic system and technological civilisation, this seems ... important.

- There's been some movement against Rule of Capture, and in particular, the concepts of unitised production (concerning oil and gas in Texas) and "certificates of clearance" (instituted by the US Department of Interior under Harold Ikes), both in or around 1931. National producers (notably Saudi Arabia) have instituted their own novel solution through a family-owned / nationalised oil industry But so far as I'm aware, the principle still stands as valid caselaw.

And, incidentally, you're correct on the airspace issue, see US v. Causby (1946) <https://en.wikipedia.org/wiki/United_States_v._Causby>. I was interested in the other elements discussed above.