how sure are you of this? I have owned a domain since 2003. a few years back a new startup named <domain> inc tried to buy it from me. they ended up getting do

how sure are you of this? I have owned a domain since 2003. a few years back a new startup named <domain> inc tried to buy it from me. they ended up getting domain.org but I checked recently and they registered the trademark. I was reading that I have only a few years to appeal it showing I am harmed by them. I did not read anywhere that they could not sue me