It's bad enough to face bullying in school and at work, so the last thing you need is to be involved in bullying someone else, especially over a name. Trademark bullying is real, and it's when a company goes after other companies for using that first company's name or something similar in situations that are clearly not a violation of trademark.
In these cases, the company suing is almost always a huge company with lots of money, and the defendant is a smaller company that may not have the financial resources to fight back. If you've found a number of trademark violations involving your company's name, it's tempting to stamp out all other mentions of it. But be careful that your company doesn't become one of those trademark bullies.
How Similar Is the Product?
First, how similar is the product that the other company is promoting, or how similar is the name itself to your company's name? If you run XYZ Import Company, and someone starts XYZ Import Company, you may have a case. But if you run XYZ Import Company and another company names itself XYZ Alphabet Tutoring, that's really not that close, despite both names using "XYZ." Think twice about suing that company for trademark infringement.
A classic case of overdoing it regarding similar names is Richard Branson's Virgin group. This conglomerate of airlines, record stores, and more has sued olive oil producers for using the word "virgin," a broadcasting company for using the word "virgin" in a TV show title, and a foundation run by the Las Virgenes School District. In other words, they went after any use of the sequence of letters spelling "virgin" even if the use of the word could not in any way be confused with their group.
When Did the Other Product Appear With That Name?
Another issue is when that other product or company started using that name. If they did not trademark that name, you may have a case that could win on a technicality. However, if they did have their name or product name well-established before your company started using the name in question, it still gets a bit murky. You may have to change your company or product name, at least in those regions where the other company already has trademarks. A good example of this is the Bookstop bookstore chain, which had to use the name "Bookstar" in some states because of existing local trademarks.
Are There Workarounds?
It's also possible that there are workarounds, where you and the other company enter into an arrangement instead of you suing them. For example, your company might offer to buy the rights to the name of the other company and pay for that company to choose and register a new name. If you foot the bill for all the trademark forms and marketing changes, it might seem expensive at first, but it could save your company's reputation by making you look like a company that's willing to work things out instead of suing at the drop of a hat.
You do want to protect your trademarks, but you also want to avoid being a bully who ends up looking clueless. If you're concerned about another company's use of a name that seems to infringe on your trademarks, speak with an intellectual property protection attorney to verify whether this is a case you need to take to court.