As of 10/9/2015, no live official trademarks were found on USPTO.gov for the exact terms/numbers
In the West, a 8-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; two flanking 8's are very lucky, even when they are non-consecutive.
This domain closes with an 8 on either side:
This domain is all about doubles, a very positive Chinese concept.
The Chinese market for numerals is HUGE.
Domains sold separately.
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