There has been various lawsuits on trademark violations in adwords. competitors are usually tempted to advertise on more popular competitor brand names. We had a client ask us to advertise on a popular competitor name but we denied it since it might back fire . There are numourous lawsuits already against google as well as other companies which violate trademarks,

We dont want to get into all these problems, we did post recently about one lawsuit where one company won over the other about a million dollar

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