IT major Cognizant's subsidiary TriZetto has filed a lawsuit against Infosys in a US federal court, accusing it of stealing trade secrets and information related to healthcare insurance software. In a lawsuit filed in Texas Federal Court, Cognizant has accused the Bengaluru-headquartered company of illegally accessing data from TriZetto's software -- Facets and QNXT -- and using the same to develop and market a competing product.