As of 10/9/2015, no live official trademarks were found on USPTO.gov for the exact terms/numbers
In this combination, "4" and "7" morph from their general negativity and in this context are actually positive.
In the West, a 6-number domain may seem slightly 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.
The Chinese market for numerals is HUGE.
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