As of 10/7/2015, no live official trademarks were found on USPTO.gov for the exact terms/numbers
In the West, a 9-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.
Despite popular belief among Westerners, "4" is not always unlucky, as shown on Travel China Guide; 4 represents the following in the natural world:
Earth, Water, Fire, and Wind
East, West, South, and North
Spring, Summer, Fall, and Winter
4 also has numerous positive connotations in Chinese culture, as listed on the above website.
In combination with other numbers (such as 54), the two negatives create a positive meaning -- in this case, "no death."
These domains are also palindromes, which means they domain read the same when pronounced from back to front, thus adding another level of mystique to the numerical pattern.
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.
These domains are sold separately.
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