As of 10/4/2015, no live official trademarks were found on USPTO.gov for the exact term/number
In the West, a 10-number domain may seem too long and mean little to average Occidentals; heck, we don't fully understand the premise, either. However...
In the Chinese market, "8" is the luckiest number.
In addition, the number "54" means "No death."
Disclosure: on the other hand, if you read the embedded number as "548," it means "no need/not going to be wealthy."
In that case, 8888548888 would also be asymmetrical. However, we'll leave numerical interpretation up to the reader.
We cannot even fathom what 8.com, 88.com, 888.com, and 8888.com are worth -- probably much more than the average investor could afford.
Long repeating 8's are prized as well. In fact, 5, 6, 7, 8, 9, and even 10+ repeating 8's are commanding excellent prices these days.
Evidently, every possible string of 8's have been registered in .com, all the way up to the longest one.
Finally, repeating 8's with other lucky numerals are becoming rare as hand registrations (fresh from the registrar) and are also highly prized.
The Chinese market for numerals is HUGE.
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