As of 10/14/2015, no live official trademarks were found on USPTO.gov for the exact term/number
348 = Wealthy for three lifetimes.
48 = Determined to prosper
84 = Forever prosperous
As an ordinary 6-number domain, these numbers may mean little to average Occidentals (other than as an easy-to-remember cool pattern); heck, we don't fully understand the premise, either. However...
In Chinese culture "8" is considered to be lucky; "3" is also lucky, representing the cycle of life: birth, marriage, and death.
Disclosure: In Chinese culture, "4" is generally considered an unlucky number because it sounds like "death."
A Western comparison: the number 13, also a harbinger of death, is considered to be an unlucky number, but, at least once a year, Westerners celebrate unlucky 13 by dressing up as ghosts, skeletons, and other scary creatures, such as Justin Bieber and Miley Cyrus.
Also, there are some instances where 4 can be represented as a lucky number.
Indeed, according to the website Travel China Guide, in China’s long history, the number 4 has been widely used and accepted as a number to represent common patterns in nature, architecture, literature, important inventions of ancient and modern China, and more.
Click and scroll to "Wide Use of No. 4" for some positive examples.
The leading lucky 348 may very well counteract the general negativity of this number.
But we'll have to allow potential buyers to arrive at their own conclusions.
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.
Chinese demand for numerals is HUGE and increasing each day.
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