If the proprietor of an earlier mark is (possibly by brand monitoring) made aware of the application of a similar or identical mark under which similar or identical goods and / or services are claimed, he may appeal against that trademark application.

In opposition proceedings the proprietor of the earlier mark, the opponent, has to explain whether the likelihood of confusion of the marks is given and what it consists of. The proprietor of the later mark is regularly given the opportunity to submit his observations and opinion. Only then a decision is made by the respective office.

Although there is a uniform grace period of 5 years in all countries of the European Union and for the Community Trademark in the European Union, in opposition proceedings the evidence of so-called genuine use is required. The grace period of 5 years allows the trade mark applicant within this period after the registration of the trademark, to start the use of it, whenever he likes. Because the careful businessman starts registering a trademark way before market introduction of the product itself, the market introduction for the product may be done in this period. Use of the brand for products before registration or right after it is not necessary. This is different, for example, in the territories of the United States or Canada. Within the opposition proceedings, the proprietor of the later mark may, if he has not found use of the earlier mark, require the opponent through application to prove the genuine use. A genuine use is given when products are sold under the brand in a sufficient amount, for which it is registered. The proof of genuine sale may be done by presenting sales efforts, such as catalogs, website, trade relations, invoices, product images and the alike.

If the opponent is able to proof the genuine use and between the compared brands and compared goods and / or services is similarity or identity, the application of the later trademark is most likely rejected, by the called Trademark Office. The opposition may, however, been restricted to certain goods and / or services.

To avoid such a contradiction method, it is always advisable to research through an Attorney or entity specialized before registration of a trademark or prior to commencement of a trademark-acquired-by-use. This research will find identical or similar marks or special markings, which may cause a conflict. The research is mostly evaluated by a special report, where a competent Lawyer will explain pros and cons for the registration of a sign.