I used to be the webmaster for my parent's HOA[0], and I bought their .com domain name when it became available (a realtor had owned it originally). They eventually hired a firm to run the site, and I pointed the domain at their nameservers, and forgot about it (paying the ~$20/year in renewals, because that's not a lot of money & I have fond memories of living there).
15 years later, I get a registered letter from a law firm – counsel to the HOA – claiming that I was violating their trademark by owning the domain name, demanding that I turn it over to the HOA, etc.
If an actual human had reached out to me, I would have happily transferred the domain. Instead, they paid a lawyer to be a dick about it – so I ignored the letter, they registered the .net, and everyone moved on.
I still keep the domain up, and redirect it to their new URL, because as long as the .com domain works, people will be using it. Which means they will still want it, and I'm not giving it to them. At least not until they ask nicely, and catch me with honey instead of vinegar.
[0]Despite this incident, their HOA is normally perfectly reasonable. It's a few hundred dollars per year to keep up with road repairs, signage, community facilities upkeep, etc.