PRAYAGRAJ, March 11 -- When Manoj Kumar Chauhan of Faizullahpur village in Uttar Pradesh's Azamgarh district smiles these days, awaiting his appointment letter, it is not jubilation but quiet vindication. This moment has taken 13 years to arrive, shaped by a nine-year legal battle that travelled from the Allahabad high court to the Supreme Court.

In 2013, he applied for one of 29,334 posts of science and mathematics assistant teachers in Uttar Pradesh's government upper primary schools. He was 43 then. Belonging to the OBC category, he received a five-year age relaxation beyond the upper age limit of 40. Armed with a B.Ed. degree, he believed he was on the threshold of a teaching career.

Instead, he stepped into a long and uncertain wai...