Our history

We are the product of a confluence of generations, combining the founding partners’ experience with the dynamism of new talent.

In a trajectory of over fifty years, we have developed a complete, specialized firm that is open to many ways of thinking.

We invest in, value and provide growth opportunities for our staff, forming a cohesive, diverse and up-to-date team.

The result is a unique vision that allows us to achieve more intelligent ways of practicing law, develop secure and innovative solutions and offer our clients a multidisciplinary and strategic perspective.

We are committed to constantly being one step ahead, taking on challenges with strategic intelligence and a strong desire to do things differently.

Our history



Oswaldo Horn, son of magistrate Oswaldo Areas Horn and nephew of magistrate Edgard Pedreira – who were both appellate court justices on the Santa Catarina Court of Justice – began practicing law in Florianópolis, SC.  Oswaldo’s role as the attorney for the Board of Trade of the State of Santa Catarina – JUCESC (1972-1975) provided him with a thorough understanding of the laws and methods for opening and operating a company in Santa Catarina.



Oswaldo served as the legal advisor to the Santa Catarina Social Security Institute – IPESC (1970-1995) and as an attorney for Santa Catarina Rural Electrification company – ERUSC (1975-1977).  In 1994, he began teaching at the Federal University at  Santa Catarina (UFSC), at the Department of Legal Process and Forensic Practice at the Center for Legal Sciences (until 2005).



The Horn Advogados Associados law firm was born. Rafael Horn added his characteristic dynamism to the daily operations in the firm and planned for organized growth beyond the bounds of traditional law practice.



After a remarkable career in the judiciary, as a judge in the first instance in Santa Catarina (1964-1979), an appellate judge in the Santa Catarina Court of Justice (1979-1990) and Minister (as Brazil’s high-level judges are known) of the Superior Court of Justice (1990-2001), Hélio Mosimann became a partner in the firm, which was renamed Mosimann, Horn & Advogados Associados. His arrival added strategic vision to the firm’s area of greatest expertise: dispute resolution.

National Recognition


Rodrigo Horn and Douglas Dal Monte joined the firm. In its first edition (2006), the Análise Advocacia 500 publication ranked the firm among the most admired in the country. The period marked the establishment of the firm as a national reference in the practice of law in Santa Catarina.



Lio Bocorny, Fábio Silveira and Ítalo Mosimann joined the firm, expanding the fields of legal practice and sectors it serves and establishing a multidisciplinary staff.

International recognition


The international publication Chambers & Partners Latin America for the first time recognized Mosimann-Horn and its partner Rafael Horn,  as references in the practice of law in Southern Brazil.  Luana Tomasi and Janaína Silveira joined the firm, expanding activities into tax law and high volume litigation.

Social arm


The MH Social program was created.  It is a pioneer in Santa Catarina in the issue of corporate responsibility of law firms and dedicates part of the company’s profits to initiatives aimed at social transformation. In the same year, the firm’s first institutional video was released.



The MH Social program received the Lumen award – created by CESA and SINSA, in the Social Responsibility category. The insurance company Seguradora Líder – DPVAT recognized the firm as one of the best in Brazil in the administration of lawsuits related to the insurance. Lucas Silva, Bruno Silva and Clarissa Cardoso joined the firm.



Mosimann-Horn conducted a rebranding process and began to position itself in the market more strategically and innovatively. Thays Tumelero and Ivan Remor enter the firm.



We have reached this new era with great confidence and are prepared to continue with you on this journey!