The full alphabet is actually registered in many extensions, from net and org to country codes like .ca,.de and .co.uk. The string is surprisingly registered in some new gtlds as well such as .site and .online.
The .com has been registered since 1999, it had been under privacy lately. Whois history shows Onyx domain solutions as the owner back in 2014.
What are they going to do with this name will be interesting, currently it does not resolve.