1867: Dominique-Antoine Casalonga, with an engineering degree from Arts et Métiers and a great interest in thermodynamics, having invented a number of mechanical devices, in particular in connection with measuring the rate of flow of liquids, became interested in how to obtain patent protection for inventions. He founded the firm both to help investors construct prototypes but also to assist them with obtaining patent protection for their inventions.

1884: Dominique-Antoine Casalonga participates in the creation of the first French association of patent attorneys (Syndicat des Ingénieurs et Conseils en Propriété Industrielle). He is one of the founding members.

1903: Doumé Casalonga, second son of Dominique-Antoine Casalonga, with a law degree takes over the management of the firm.

1934: Doumé Casalonga is elected chairman of the French association of patent attorneys (Compagnie des Ingénieurs Conseils en Propriété Industrielle).

1940: Doumé Casalonga becomes an Expert in industrial property before the Paris Court of Appeal.

1941: Alain Casalonga, son of Doumé Casalonga, with an engineering degree from Ecole Centrale de Paris and a Doctorate in law, takes over the management of the firm and develops its activity soon after the end of the second world war by visiting new clients in Europe and in USA thus developing important relationships with a large number of multinational companies, which remain clients of the firm today.

1969: Axel Casalonga, son of Alain Casalonga, French and European Patent, Trademark and Community Design Attorney, becomes partner.

1978: The Munich Office is opened for representation before the European Patent Office.

1978: A suboffice is opened in Grenoble to assist the local industry and research laboratories.

1981: The CASALONGA firm takes over the activities of JOSSE & PETIT, a well-known industrial property firm in Paris. The name of the firm is changed to Bureau D.A. CASALONGA-JOSSE.

1988: Gérard Dossmann, French and European Patent, Trademark and Community Design Attorney, becomes partner.

1996: The Alicante Office is opened for representation before the OHIM in Community Trademark matters and latter on Community Design matters.

2003: Francis Zapalowicz, French and European Patent Attorney, focussing on electronics, becomes partner.

2005: Creation of the law firm CASALONGA AVOCATS by Caroline Casalonga, attorney-at-law at the Paris Bar and European Trademark and Community Design Attorney, eldest daughter of Axel Casalonga.

2006: Olivier Delprat, French and European Patent Attorney, focussing on mechanics and electronics, becomes partner.

2006: Arnaud Casalonga, son of Alain Casalonga, attorney-at-law at the Paris Bar and European Trademark and Community Design Attorney, and his team of IP lawyers join CASALONGA AVOCATS.

2007: Karina Dimidjian-Lecomte, attorney-at-law at the Paris and New York Bars and European Trademark and Community Design Attorney, becomes partner.

2009: Jürgen Neugebauer, Patentanwalt, European Patent, Trademark and Community Design Attorney, becomes partner of the Munich Office.

2010: The Munich Office of CASALONGA-JOSSE, becomes "CASALONGA & PARTNERS".

2010: Virginie Martin-Charbonneau, French and European Patent Attorney, focussing on chemistry, and Marianne Gabriel, attorney-at-law at the Paris Bar and European Trademark and Community Design Attorney, become partners.

2012: Bureau D.A. CASALONGA-JOSSE becomes CASALONGA & ASSOCIÉS.

2012: Jean-Baptiste Lecœur,attorney-at-law at the Paris Bar and European Patent Attorney, focussing on chemistry, become partner.

2014: A suboffice is opened in Toulouse by Matthieu Sagnes and Patricia Ledrut, French and European Patent Attorneys, focussing on mechanics, to assist the local industry and research laboratories.

2015: Cristina Bercial-Chaumier, attorney-at-law at the Alicante Bar and European Trademark and Community Design Attorney, becomes partner of Alicante Office. Gwennhaël Le Roy and Julien Thon, French and European Patent Attorney, focussing respectively on chemistry and mechanics, become partners.

2017: A suboffice is opened in Lyon.

2017: Floriane Codevelle, attorney-at-law at the Paris Bar and European Trademark and Community Design Attorney, becomes a partner.

January 1^st, 2018: CASALONGA becomes the 1^st French law firm of lawyers and patent and trademark attorneys. CASALONGA & ASSOCIÉS and CASALONGA AVOCATS merge to become CASALONGA.

2018: A suboffice is opened in Montpellier by Laurence Schardt, French and European Trademark and Design Attorney.

2019: A suboffice is opened in Beaune.

2019: The Toulouse suboffice is expanding with the arrival of Pascaline Vincent, attorney-at-law at the Toulouse Bar, who joins Matthieu Sagnes, French and European Patent Attorney, focussing on mechanics.

2019: CASALONGA leaves its historic offices on avenue Percier to move to the in the 6^th arrondissement of Paris, rue de Fleurus.

2022: A suboffice is opened in Pau by Patricia Ledrut, French and European Patent Attorney, focussing on mechanics.

2023: Pascaline Vincent, attorney-at-law at the Toulouse Bar, becomes a partner.

2024: Augustin Le Tourneau and Ghislain de Trémiolles, French and European Patent Attorney, focussing on emerging technologies and electronics join the firm as partners.