Download all Forms (Models) of Certificates for Kerala PSC. For Downloading go to the following link and then click File menu and select Downloadoriginal. 1. Form of Community Certificate for Other Backward Classes (OBC). OBC Community Certificate 2. The Form of Caste Certificate For SC/ST. SC/ST Certificate 3. The Experience Certificate format. Experience Certificate 4. Model Form of Nativity Certificate. Nativity Certificate 5. Form of Certificate to be produced by Other Backward