<h1>IndiGo seeks refund of over Rs 900 crore Customs duty on re imported aircraft engines and parts.</h1> IndiGo seeks refund of over Rs 900 crore Customs duty paid on re imported aircraft engines and parts after overseas repairs, alleging an unconstitutional double levy because it also paid GST under the reverse charge for repair services. A Customs tribunal previously held re imports should not bear Customs duty again and treated a later exemption amendment as prospective. After paying duty under protest on more than 4,000 bills, IndiGo's refund claims were refused pending reassessment of each bill.