How will I know if a someone's applying for a trademark similar to mine?

If you want to find out if a third party is applying for a trademark that might be similar to yours, there are a couple of ways to monitor this.

1. The IP office with which you registered your trademark might notify you in case their examining attorney finds a similarity between your mark and the new mark. However, we wouldn't recommend relying solely on this method. For example, if you own a trademark in Germany, you won't be notified by the EUIPO, even though your German trademark allows you to oppose EU applications.
2. You can conduct a trademark search yourself. You can do so based on multiple criteria, e.g., the classes of goods and services. Trademark databases are public, so anyone can perform such a search. You can find information about the owners of the trademarks as well as their legal representatives. Moreover, you can find all the important dates, such as the date of filing of a particular trademark application.
   
   Make sure to adjust the periodicity of your search to the length of the opposition window in your jurisdiction(s). In some jurisdictions, it might be sufficient to perform the search once a month, while in others, this wouldn't give you enough time to raise an opposition before the window closes.
3. You can use trademark watch services provided by different companies. Such services are often paid; however, they might be very helpful in case you want to keep an eye on your competition. How it works is you sign up for the service and get notified if a similar or identical trademark application is filed in a jurisdiction you wish to monitor.

If you are interested in outsourcing your trademark monitoring, you can check our Trademark watch.