ATL

OK experts, here is a question for you.
We have 3 domain names. All owned by by different parties. I will use examples not to post originating domains. We will use for example the following:
a.com
ab.com
abc.com

Say (for example) I owned abc.com and the owner of ab.com said I am infringing upon his domain name of ab.com Since his copyrighted word of 'ab' is in my domain. Personally I think it's total bullshit but he tried.

Now my question, would this be true?
If it is true then would he the owner of 'ab.com' then be infringing upon 'a.com'?

I hope I make sense and get some experienced answers here.

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