Named Étoile at the Opéra national de Paris in 2002, Clairemarie Osta won her first dance prizes at the Conservatoire Régional de Nice and the Conservatoire Supérieur de Paris (CNSMDP). As a child, she was also French tap dance champion. She won the Grand Prix of the Mediterranean Competition in Grasse (France) as well as the Technique and Interpretation Prize and the Senior Bronze Medal in Varna (Bulgaria).
Clairemarie Osta has worked with Rudolf Nureyev, Carolyn Carlson, John Neumeier, Jiri Kylian and Jerome Robbins, and has inspired many choreographers to create roles especially for her: Roland Petit wrote the role of Marie in Clavigo and Angelin Preljocaj that of L'Eveil in Siddhartha. Other roles include Amoveo by Benjamin Millepied, Appartement by Mats Ek, and Pas-Parts by William Forsythe. For Jean Claude Gallotta, she was the wife in Nosferatu, and for Nicolas Le Riche, the Moon in Caligula. In 2008, she played Anaïs Nin in the short film Anaïs Rushes, by Clara Ballatore.
In 2012, the documentary Les Adieux (A. Dreyfus) retraced the preparations for her final performance at the Paris Opera as Manon in Kenneth McMillan's I'Histoire de Manon. A year later, she was appointed Director of Choreographic Studies at the Conservatoire National Supérieur de Musique et de Danse de Paris.
In 2014, Clairemarie Osta performed M. & Mme Rêve by Marie-Claude Pietragalla and Julien Derouault, before travelling around France with the production of Itinérances, directed by Nicolas Le Riche. As part of a work commissioned by the Théâtre des Champs-Elysées, Nicolas Le Riche created his solo in Une Après-midi... to the music of Claude Debussy, and the duet Odyssée set to music by Arvo Pärt, which became the subject of a short film directed by Vincent Perez in 2016.
In 2015, Clairemarie Osta co-founded LAAC - l'Atelier d'Art Chorégraphique, at the Théâtre des Champs-Elysées.
In 2016, she created with Nicolas Le Riche PARA-II-ELES, a poetic dance-performance set to music by Matthieu Chedid as part of Transcendances at the Théâtre des Champs-Elysées, and subsequently toured it. Clairemarie Osta chaired the jury for the Nijinsky competition in Deauville for three years and is also a member of the jury for the Prix de Lausanne and the Tanzolymp in Berlin, as well as being a member of the jury for a university doctorate.
She is a member of the Association Française des Maitres en Danse Classique. She has been invited to the Boris Eifman School in Saint Petersburg as a consultant.
From January 2018 to 2022, she was ballet director at the Royal Swedish Ballet School in Stockholm.
Since 2020, Clairemarie Osta has had the pleasure of remounting the Nureyev Foundation's productions of Swan Lake and Don Quixote. She is delving into this exceptional heritage to pass on to new generations. She is also helping to train dance teachers at the invitation of Stockholm University.
Going out to meet dancers, she teaches at the Ballet du Théâtre de l'Opéra de Rome, the Boston Ballet, the Royal Swedish Ballet, the John Cranko School and the Finnish Ballet School. She accompanies dancers at the Paris Opera in their preparation for the famous internal competition and coaches some of them in the production of Nureyev's The Nutcracker.
Today she is pursuing her dreams by adding to her choreographic experience "L'autre moitié du songe..." (The other half of the dream...). (Text by Alicia Gallienne, music by Simon Bång). She continued to learn and became a certified MUNZ FLOOR® coach.
Clairemarie Osta is a Chevalier de Ia Ordre de Ia Légion d'Honneur, Chevalier des Arts et Lettres and Officier de l'Ordre du mérite.