Trademark owners may face several challenges, including infringement, where other parties use a similar mark without permission. This can dilute the brand and cause consumer confusion. Another challenge is the international protection of trademarks, as a mark registered in one country may not be protected in another. Owners must be vigilant in monitoring their trademarks and enforcing their rights to prevent misuse. Additionally, maintaining the trademark by meeting all legal requirements and renewals can be cumbersome but is necessary to retain ownership.