In general terms, the owner of a well-known trademark not registered with the relevant PTO is allowed by Law to prevent others from obtaining a trademark registration for an identical or similar mark.

一般情况下，未注册的驰名商标所有人，根据法律可以禁止他人注册相同或相似的商标。

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The federal bar against registration of a mark resembling that of a prior user is primarily a codification of common law.

联合禁止注册与在先使用人的商标之相似商标主要源自习惯法的法典化。

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Despite the gauntlet that is the United States Patent and Trademark Office, many of the trademarks which are allowed by the Trademark Office are opposed by some competitor in an administrative law tribunal because they feel the mark violated one of the rules of registration.

FORBES: Gang Green: Rules Are Tightening. Don't Say Green If You Don't Mean Green.