The public interest must be taken into account when reaching an agreement on the coexistence of trademarks. This is often the case in situations where two medical companies carry the same brand for unique products, which could cause confusion and have serious consequences for consumers. Companies must also comply with the rules on cartels and abuse of dominance. Courts may find that similar marks can affect competition in the marketplace. Brand co-existence describes a situation in which two different companies use a similar or identical brand to market one product or service without necessarily interfering with the activities of the other. This is not unusual. Brands are often used by small businesses in a limited geographic area or with a regional clientele. Almost all French cities with a train station, for example, have their own buffet restaurant at the station. Often, trademarks are made up of the name of the person who started a business, and where that name is common, it is not uncommon to find similar companies under the same name or name. None of this should give rise to conflicts or disputes as long as the brands concerned continue to fulfil their primary mission of distinguishing the goods or services for which they are used from those of competitors. Companies should also be aware of competition and cartel rules: courts may find that their brands of similar products, which are confusingly congruent, are harming competition in the market. A formal agreement on trademark coexistence recognizes the rights of both parties to use the trademarks contained in the agreement for marketing purposes.
The agreement may include a breakdown of the regions in which companies using contracting parties can use the trademark, the methods in which the mark can be used or the categories of products and services for which the trademark can be used (in conjunction with the Madrid system for international trademark registration).  An agreement on trademark co-existence should include the following: A party that is clearly a follower brand user (not the first party to use a trademark) may have no choice but to seek approval agreement from the previous user of the trademark (the first party that generally uses and registers a trademark in the trade). However, if the bargaining power between the parties is more regular, a co-existence agreement detailing the issues important to both parties is probably in the interest of all. The bargaining power for the use of the trademark can be created by the status of an older user, by a known or known brand, or by the ownership of additional trademarks that the other party may be interested in limiting.