I bought a new domain for my business and there was no trace of any old business name when researching connected to that domain. After about 6 months I received some data from an old client of theirs. It had a company name so I was able to let someone from that company know, as well the sender and I deleted the data before reading it. I guess you have to think what did you use it for, who might send data that identifies you etc. You never know who might buy it.

I remember reading an article but can't find it now. A researcher bought tons old domains from government and local departments that had shut down or changed names, and managed to get some interesting information!