I don't see how. Its a free market. IMO you'll jsut have to out bid him. Now if he was an affiliate of yours you could require him to not do that or pull his ticket, but otherwise I don't think you have any grounds legally.
It is just the internet and everything is just hard to definite. Just find some measures to protect your profit. www.china-seller.com
If your name is trademarked in some fashion you can write to Google and prevent them from bidding your your trade name. This is old case law. E.g. Coke cannot lawfully bid on Pepsi's trade name to divert traffic of people intending to go to Pepsi to the Coke web site. If your business name is "mywebsite" then it's another story and it's easy to see the reasons why.
From Google -- As a courtesy, we are happy to investigate trademark complaints raised by trademark owners. To initiate an investigation, follow the trademark complaint steps outlined at http://www.google.com/tm_complaint_adwords.html. Please note, as stated on our trademark complaint procedure page at http://www.google.com/tm_complaint_adwords.html#1, we do not investigate keyword complaints for U.S. or Canadian trademarks. As a result, we will not be able to remove ads that are using your trademark as a keyword if your trademark right are in the U.S. and/or Canada. Our terms and conditions with advertisers prohibit intellectual property infringement by advertisers and make it clear that advertisers are responsible for both the keywords they choose to generate advertisements and the text that they choose to use in those advertisements on Google. You are more than welcome to contact advertisers directly to resolve any trademark disputes that you have. Trademarks and our search results: Our trademark complaint procedure applies only to the use of trademarks in ads, which are clearly marked as sponsored links on our results pages. We do not take action on objections to the use of trademarks in sites that appear in our search results. For any such objections, please contact the site owner directly. -- Regarding this, we will be contacting the competitor site and ask them what's the deal.
I prevented a competitor from buying our name as an adword and using it to wrongfully redirect traffic. Take a look at the trademark complaint procedures in the URL you provided.