摘要股份回购和现金分红是公司支付政策的两架马车。然而，我国股份回购的限制较多，前期实施股份回购的公司较少，相应的学术研究也较为缺乏。随着我国资本市场改革的推进，股份回购的制度也在持续改善，有关研究越来越多。本文的主体内容是研究金融去杠杆背景下公司股份回购的动机、影响因素与其信息内涵。本文回顾国内外相关研究文献，整理关于股份回购的多个动机假说及其影响与后果，关注通过研究不同公司股份回购方式对市场反应影响的差异来揭示股份回购的信息内涵。本研究一方面有助于在理论上检验金融去杠杆下我国上市公司股份回购的动机与影响因素，另一方面有助于在实践上对我国股份回购市场监督提供政策建议。同时，本研究还探讨了投资者对国有与非国有上市公司的股份回购的市场反应是否存在差异。本文使用2014年1月到2018年8月在深交所和上交所公告实施股份回购的A股上市公司为样本，通过研究得出以下结论：（1）相比场外交易，公开市场股份回购的正向市场反应更大，并且，相对于非国有企业，国有企业在发布股份回购公告日事件窗口前后市场会出现更加强烈的反应；（2）在公开市场股份回购这一类型中，股份回购的规模越大，投资者累积超常收益率越高。本研究探讨了我国资本上市的股份回购是支撑“功能锁定”假说或是支持“有效市场”假说的理论问题，研究得到的实证证据更支持“有效市场”假说。同时，本文对股份回购的监管实践也提供了政策建议。关键词：股份回购；回购动机；市场反应AbstractSharerepurchaseandcashdividendsaretwocarriagesofthecompany'spaymentpolicy.However,therearemorerestrictionsonChina'ssharerepurchase.Therearefewercompaniesthatimplementsharerepurchaseintheearlystage,andthecorrespondingacademicresearchisalsolacking.WiththeadvancementofChina'scapitalmarketreform,thesystemofsharerepurchasehascontinuedtoimprove,andmoreandmoreresearchhasbeendone.Themaincontentofthispaperistostudythemotives,influencingfactorsandinformationconnotationofthecompany'ssharerepurchaseunderthebackgroundoffinancialdeleveraging.Thispaperreviewsrelevantdomesticandforeignresearchliterature,sortsoutmultiplemotivationhypothesesaboutsharerepurchaseanditseffectsandconsequences,andfocusesonrevealingtheinformationconnotationofsharerepurchasebystudyingthedifferencesinmarketreactioneffectsofdifferentcompanies'sharerepurchasemethods.Ontheonehand,thisstudyhelpstotheoreticallytestthemotivesandinfluencingfactorsofChina'slistedcompanies'sharerepurchaseunderfinancialdeleveraging.Ontheotherhand,ithelpstoprovidepolicyrecommendationsforChina'ssharerepurchasemarketsupervisioninpractice.Atthesametime,thisstudyalsoexploreswhetherthereisadifferenceinthemarketresponseofinvestorstosharerepurchasesbetweenstate-ownedandnon-state-ownedlistedcompanies.ThispaperusestheA-sharelistedcompaniesannouncedbytheShenzhenStockExchangeandtheShanghaiStockExchangetoimplementsharerepurchasefromJanuary2014toAugust2018.Thefollowingconclusionsweredrawnthroughresearch:(1)Openmarketsharerepurchasecomparedwithover-the-countertransactionsThemarketismoreresponsive,andthemarketreactionofstate-ownedenterprisestosharesharerepurchaseannouncementsisstrongerthanthatofnon-state-ownedenterprises;(2)intheopenmarketsharerepurchasetype,thelargerthesharerepurchase,thehighertheinvestor'scumulativeextraordinaryrateofreturn.ThisstudyexploresthetheoreticalrepurchaseofChina'scapital-listedsharerepurchasetosupportthe"function-locked"hypothesisorthe"effectivemarket"hypothesis.Theempiricalevidenceobtainedfromthestudysupportsthe"effectivemarket"hypothesis.Atthesametime,thispaperalsoprovidespolicyrecommendationsfortheregulatorypracticeofsharerepurchase.Ke...
