I found my client VAT monthly return was incomplete / mistake for FY 2007-2008. The assesse is from TamilNadu. They completely ommitted huge purchases made from unregistered dealer in their monthly VAT return as the law was to them. But no tax liability accures becasue when a purchases are made from unregistered dealers the tax liability accures on the purchaser but he can simulateously claim input credit. Do i need to file a revised monthly VAT return now? Is it necessary to file revised return as there is not actual VAT liability ? What is the time limit to file revised return? If the time limit for filing revised monthly VAT retrun is elasped as it pertain to FY 2007-2008 what is the option left i.e can revised return can be filing even after the expiry if time limit? Can the assessing officer can claim tax liability plus penalty on unregistered purchase and dont give input credit becuase the revised return is not filed within prescribed time? Is there any case law for this for defend his claim ?