Son of Théophile Thomassin (saddle maker) and of Auguste Joséphine Bellaire, he serve his apprenticeship with C. N. Bazin in Mirecourt.
It was at this point that Claude Thomassin set up his own atelier at 37 Rue de Paradis in Paris.
Although he continued to produce some bows for his former employers, much of his output from 1901 onwards was branded with his name "Claude Thomassin" or sometimes "C.Thomassin à Paris".
He was Louis Thomassin first Cousin and not his son as many books incorrectly report.
[3] "C. Thomassin's work is highly prized and respected for playability and beautiful workmanship" – Filimonov Fine Violins