Under what circumstances an application for advance ruling will not be allowed ? Is advance ruling binding on the income-tax department? When does an advance ruling become void?

Application for advance ruling shall not be allowed when the question raised in the application: is already pending in applicant's case before any Income Tax Authority. involves determination of fair market value of any property. relates to a transaction which is designed for avoidance of income tax. Advance ruling shall have binding only on the Commissioner and the Income Tax Authorities subordinate to him in respect of the applicant and the transaction. The advance ruling shall be void ab-initio, if it is subsequently found to have been obtained by fraud or misrepresentation of facts.