washington republican lawmakers call u.s. treasury secretary jack lew monday overhaul propose regulations intend crack american company try reduce u.s. tax rebasing abroad process know inversion separate letter top republicans senate finance committee house ways mean committee warn monday treasury move quickly adopt regulations prevent overseas mergers know tax inversions u.s. firm relocate headquarter countries low corporate tax rat propose regulations completely overhaul would damage economy increase barriers investment american businesses innovators interfere growth ... good-paying job say letter lew ways mean committee chairman kevin brady republicans panel allow happen write regulations propose april treasury indicate intend move swiftly finalize rule industry leaders fear rule could place permanently early september one new inversion rule already impose temporary basis challenge month federal court business group include u.s. chamber commerce brady republicans include senate finance committee chairman orrin hatch train sight proposals industry officials say would swamp business new red tape cripple internal cash management operations company involve tax inversions prudent way move forward give complexity subject matter give many significant substantive concern point give procedural irregularities issue regulations re-proposed form hatch say letter lew propose debt-equity rule aim stop practice know earn strip occur newly invert company elude u.s. tax move profit overseas tax-deductible interest payments loan foreign parent treasury propose require debt interest payments convert stock dividends tax deductible critics say regulations propose could play havoc internal finance range unsuspecting businesses multinational corporations limit partnerships republicans urge u.s. treasury overhaul tax inversion proposals