As of 10/9/2015, no live official trademarks were found on USPTO.gov for the exact terms/numbers
In this combination, "4" morphs from its general negativity and in this context is 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; "2" is also considered very lucky: "Good things come in pairs."
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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