If you do your best effort to determine whether a trademark exists, you will limit your liability but if you do find something and use the trademark anyway you

If you do your best effort to determine whether a trademark exists, you will limit your liability but if you do find something and use the trademark anyway you will increase your liability if that's discovered. If multiple companies are sharing the trademark and any of them have semi sentient legal teams, they likely have some sort of agreement in place (but you have no way of knowing). Failure to do so would greatly weaken the trademark claim. > ...potential trouble only depends on an adversary's willingness to litigate, In order to protect your trademark, you have to be willing to litigate. > Is it such a minefield that it isn't even worth bothering? Is the name so critical to your idea that it is worth bothering?