Appeal procedure: Mandatory pre deposit, prescribed forms and strict time limits govern service tax appeals and cross objections. Any person aggrieved by an adjudicating authority may appeal to the Commissioner (Appeals) in Form ST-4 within two months (plus one month condonation), with a mandatory pre-deposit at the first stage; the Commissioner (Appeals) may enhance service tax, interest or penalty after giving a reasonable opportunity. Appeals to the Appellate Tribunal are in Form ST-5 (assessees) or ST-7 (department), filed within three months (four for committees), with cross objections in Form ST-6 within 45 days; the Tribunal may admit belated filings on sufficient cause and fees are prescribed for appeals.