Jean Pinchon was licentiate in canon law at Paris before 1414, archdeacon of Josas in 1418, and at Melun; he took possession in 142, of a canonicate at Rouen that he had obtained about 144; on this occasion he made his submission to Henry V.

We note that he took the title of scribe and abréviateur of apostolic letters.
On November 9, 1422, he challenged letters of appeal to the Pontiff concerning a dispute in which he felt himself to be wronged, and he fought for the nomination of Jean de la Rochetaillée as Archbishop of Rouen; when a majority was obtained by Nicolas de Venderès, he demanded the nomination of new officers for the archbishopric during the vacancy of the See, those who had been named seeming suspect to him.

He was a deputy to the Council in 1424, and was named, December 3, 1429, vicar-general during the vacancy of the See. This battling cleric, who had to reconcile himself with his confrère, Jean de Besançon, against whom he had spoken injuriously, enjoyed the full confidence of the English.

Bedford entrusted him with presenting to the Chapter the charter by which the English duke made himself the second founder of the Carmelites at Rouen (January 9, 1431).

Jean Pinchon coveted also the canonicates of Tournai and Evreux; he must have died at Paris before June 25, 1438. He was an assiduous judge at the Trial, and judged in accordance with the theologians of Paris and referred himself to the authority of Guillaume Le Boucher.