According to the guidelines, a policyholder will have to approach an insurer 45 days before his policy with the old insurer expires, to enable the new company consider his application. In a circular, the IRDA said that the acquiring insurer will verify the claims history from the common database, which will have two years of claims experience.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/new-norms-make-it-easier-change-health-insurer
[2] http://admin.indiaenvironmentportal.org.in/category/author/bv-mahalakshmi
[3] http://admin.indiaenvironmentportal.org.in/category/newspaper/financial-express-new-delhi
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-insurance
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/insurance-industry
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health