As of 10/8/2015, no live official trademarks were found on USPTO.gov for the exact term/number
In Chinese culture repeating 9's (consecutive 99's and 999's) are considered to be lucky.
As an ordinary 2-letter/5-number domain, this pattern may mean little to average Occidentals (other than as an easy-to-remember cool pattern); heck, we don't fully understand the premise, either.
In Chinese culture, the number "9" represents longevity.
Chinese demand for a mix of letters and numerals is increasing each day.
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