Appeal to Supreme Court: appeals under customs law proceed subject to certification and strict limitation periods for civil appeals and SLPs. Appeals to the Supreme Court arise from specified High Court judgments and certain appellate authority orders concerning duty rate or valuation questions. Civil appeals must be filed within sixty days of receipt of the order; where certification to appeal is not sought, aggrieved parties commonly file a Special Leave Petition under Article 136 within ninety days. Time spent procuring certified copies is excluded from limitation. Proposals for filing SLPs and civil appeals are examined and processed by the Board on receipt from field formations with Chief Commissioner approval.