It might end up being worth it. In 2006 we registered twingly.com, while a startup in the US registered twing.com. Twing and Twingly are similar enough to sue for cease and desist, especially since our businesses areas overlapped very much. Us being a search engine for blogs and them a search engine for discussion fora.<p>By the time we found out about each other, we had registered Twingly as a trademark in EU and Twing was pending registration in the US. Thus, we had symmetrical leverage on each other and the negotiations for an agreement of global, peaceful co-existance was hassle-free. It was in both our interests to get it in place. None of us had in their minds to attack the other but didn't know to trust the other in the long run. If you end up building the next Google you don't want someone around with the ability to take an easy shot at your business.<p>To conclude, I think both of our companies were happy we registered our trademarks early on.<p>Since then however, Twing was deadpooled after their financers pulled the plug. On another note, Twitter and Twine were also started in 2006, without anyone of us being aware of each other until after some time. It was simply a year for startup names starting with Twi, as it seems.