This　paper　develops　an　interval　noncooperative-cooperative　biform　game　(referred　to　as　the　interval　biform　game　in　short　hereafter)　model　that　accounts　for　both　strategy　choice　and　coalition　formation　while　also　addressing　profit　allocation　with　interval　coalition　characteristic　values.　This　interval　biform　game　consists　of　four　elements:　a　finite　set　of　players,　their　strategy　choices,　coalitions,　and　interval　coalition　characteristic　functions,　and　contains　both　noncooperative　and　cooperative　parts.　The　payoffs　of　different　strategies　are　not　directly　given　a　priori　in　the　noncooperative　part　but　obtained　by　solving　interval　cooperative　games　in　the　cooperative　part.　To　solve　the　interval　cooperative　game,　we　extend　a　real-valued　weighted　equal　contribution　division　(WECD)　approach　to　an　interval-valued　version.　Subsequently,　an　interval　acceptability　degree　comparison　method　is　introduced　to　compare　the　interval　payoff　values.　We　then　establish　existence　and　necessary　conditions　of　pure　strategy　Nash　equilibriums　and　derive　a　condition　for　a　Nash　equilibrium　to　be　efficient　in　an　interval　biform　game.　Finally,　numerical　examples　are　furnished　to　illustrate　the　validity　and　applicability　of　the　proposed　framework.　©　2022　Elsevier　Inc.