Phan tich su bien dong cua gia sau khi doanh nghiep thong bao mua lai co phieu tai Viet Nam
Truong Dai hoc Gong nghe th6ng tin va Truy6n th6ng, Dai hgc Thai Nguyen
Bdi bdo Id san phdm cua Nghien ciiu khoa hoc cdp casdsd T2019-07-27, duoc tdi tra bai trudng Dgi hoc Cdng nghe Thdng tin vd Tmyin thdng, Bai hoc Thdi Nguyen.
Bdi bdo ling dyng phuong phdp nghien eiiu su kien (Event Study) vd md hinh dd phan ti'eh dnh hudng efla viee mua lai ed phldu tdi gld c6 phldu cfla doanh nghiep. Tae gid tidn hanh nghien cflu vdi dii lieu Id cac chuong hinh mua lai cd phldu cua tat cd cdc cdng ty nidm ydt tren thj hudng ehiing khoan Viet Nam tii nam 2008 den 2017 nhdm phan tich bidn ddng gia trong thdi gian ngdn hgn xung quanh thdi giein thdng bao mua lgi cd piiidu cfla doanh nghidp bang phuang phap nghien eiiu su Iden va md iiinh. Trong 2 ngay xung quanh viec ede doanh nghidp Viet Nam mua Igi cd pliidu thi gid cd phldu hau nhu Ithdng cd phdn ling vdi ed hai sg kien la doanh nghiep kdt thflc vide thue hien mua lai ed phldu va doanh ngiiiep thdng bdo kdt qua mua lai ed phldu.
LMoflau
Hoat ddng mua lai ed phieu ngay cang hd ndn phd bidn tgi Viet Nam, vi vdy nhdm giflp cho hoat ddng nay duge dien ra mdt each minh bach va hieu qua, Chinh phu \^iet Nam da ban hanh nhiing van ban ludt va dudi ludt dd qudn ly hogt ddng ndy. Mdt trong nhiing van bdn lugt ddu tidn quy djnh ve hoat dgng mua lai co phldu id Nghi ^inh 58/2012/ND-CP ban hanh ngay 20/7/2012, ed hieu luc ngay 15/09/2012. Nghj djnh 58/2012/ND-CP quy dinh cac ndi dung hong mua lai ed phldu eua cdng ty dgi chung d Muc 2 — Chuong III nhu cdc didu kien mua lai cd phidu, cae trudng hgp khdng duoe mua lai ed phidu ldm ed phidu quy. Sau Nghj djnh 58/2012/ND-CP, Nghi dinh 60/2015/ND-CP duge ban hdnh ngdy 26/6/2015, cd hieu igc ngay 01/09/2015 nhdm siia ddi, bd sung mdt sd didu eua Ngh! dinh sd 58/2012/ND-CP. Bi cung vdi sg phdt tridn cfla hogt ddng mua lgi co piiieu, Chinh phu da ban hdnh tiiem nhidu nghi djnh va thdng tu mdi de bd sung cac quy dinh vd mua lgi co phidu. Thdng tu I62/2015/Tr-BTC ban hanh ngay 26/10/2015, cd hieu luc ngay 15/12/2015 da bd sung cdc dl^u kidn mua lai cd piiieu vd cdc trudng hgp khdng duge mua Igi c6 phidu cung nhu quy djnh tiidm cde bude trong quy trinh mua lgi c6 phidu cfla eae cdng ty dai chung Viet Nam tgi Chuong V — Mua Igi cd phidu, ban ed phidu quy bao gdm tai lidu bdo edo mua lgi c6 phldu; bdo cdo va cdng bd tiidng tin mua lai cd phieu; thuc hidn mua Igi c6 phidu; tiiay doi vide mua lgi cd phidu; qudn ly vd hgch todn eo phidu quy; trdch nhidm cfla cdng ty ehung khodn vd Sd Giao djch Chflng khoan. Thdng tu 203/2015/Tr-BTC ban hdnh ngay 21/12/2015, cd hidu
ige ngdy 01/07/2016 tiep tye bd sung nhiing quy dinh cho hoat ddng mua lgi cd phldu.
Tuy nhien, cac quy dinh phap luat van bde Id han chd khi ap dgng vao thue te. Cae van ban phap ludt mdi ehi quy dinh khdi lugng cd phidu tdi da ma khdng quy djnh khdi lugng cd piiidu tdi Uiidu cdng ty duge phep mua lai hong ngdy hodc hong mdi tuong quan vdi khdi lugng giao djch eua nhiing cd phieu nay hong nhung ngay hay thang lidn trude. Ngoai ra, ludt khdng quy dinh didu kien cy the dugc thay ddi kd hoach mua lai va ehi yeu cau chiing minh cd ngudn vdn de tdi trg md Ididng yeu cdu cd lugng tien nhan rdi. Bdn eanh dd, do tinh minh bach thdng tin chua cao, viee xu phat cac cdng ty khdng lam dflng quy djnh cung rdt khd khan.
HJBli 1. Tinh hiiib tboDg bao mua lai c6 pbieu cuu cic doanli Dgblfp niem yet tren tb) tmong chang UIOHD Vift Nam giai dojn 2008 - 2019
Ngiian: Tac gia long hop
Tinh hinh thdng bdo mua lgi cd phidu tgi Viet Nam cd xu huong tdng. Ndm 2011 la ndm sd lugng thdng bdo mua lgi c6 piiidu nhidu nhdt trong giai dogn 2008
— 2018 vdi 203 thdng bdo mua lgi, cao gap 2 ldn so vdi trung binh m6i nam cfla cd giai dogn. Sd lugng cac
H Tt C H A U A - T H A I
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NGHIEN CUU
RESEARCH
thdng bdo mua lai cd phidu ed xu hudng gidm kd tii
^ d m 2012 vdi 122 thong bdo nhung chi edn 60 va 64 Hj^ng bdo hong nam 2013.
2. Dir iieu va phumig phap nghien ciiu
3. Ket qua nghien ciiii
Bdng phuong phdp nghien cflu su kien va kidm dinh t-test, ngiiien eiiu dua ra ket qud anh hudng cfla ngdy kdt thuc viec thuc hien mua lai cd phieu va ngdy thdng bdo ket qua mua lai ed phldu eua doanh nghidp Mdu nghidn eiiu ban dau bao gdm 311 thdng bao tiidng qua danh gia eiii sd CAR (lgi nhuan bat tiiudng mua bdn lai cd phidu tren thi trudng md duge thuc tich luy). Khae v6\ cae thi hudng tdi ciiinh tidn tien hidn bdi eac cdng ty duoc niem yet hen san chiing hen the gidi khi ma eac thdng bao vd ke hoach mua khoan Vidt Nam trong giai dogn tii 2008 — 6/2019 lgi ed phldu va ngay kdt thue vide thue hidn mua lai cd dugc cung cap bdi tren trang web cfla UBCKNN. Tuy phidu deu dugc cdng khai hdn thj trudng thi tai Vidt nhien, nghien ciiu tien hanh loai bd mgt sd mdu Nam, ngay doanh nghiep thdng bdo mua lai cd phidu ngiiien eiiu khdng dfl didu kien de phfl hgp vdi md trong bude 5 quy trinh mua lgi cd phieu khdng duge hinh va phuang phdp nghidn eiiu dgng eo cac doanh cdng khai ma thj trudng vd cdc nha ddu tu chi tidp cdn nghiep thue hien mua lai ed phidu va dnh hudng cfla dugc thdi gian doanh nghidp ket thfle vide thue hidn mua lgi cd phidu len hieu qua hoat ddng kinh doanh mua lai ed phidu (bude 6 trong quy trinh mua lgi cd eua doanh nghidp. Cdc didu kien logi bidn bao gdm;
Thii nhdt, nghien eiiu loai bd cae thdng bao bdn cd phidu;
Thii hai, nghidn ciiu loai bd eae thdng tin mua lai c6 phidu tren thi trudng md chua hoan Uianh viee mua lai cd phidu;
Thii ba, nghien cuu logi bd nhiing thdng bao mua lgi cd phie'u khdng cd dfl thdng tin dd tinh todn nhu thdng tin ve so lugng cd phieu dang luu hanh, sd lugng cd phieu dang ky mua lai vd sd lugng cd phidu thuc hidn mua lai.
Sau khi Igc du lidu, mdu quan sdt cdn lgi Id 76 thdng bdo mua lgi cd phidu, trong dd ed nhiing cdng ty thuc hidn niildu lan mua lai ed phieu trong mdt nam. Vi vdy vdi mau quan sdt ldp lgi nhidu ldn trong mdt nam, nghidn eiiu cdng gdp khdi lugng mua lai cd phieu trong tdt cd cdc ldn thdng bdo thanh mdt mdu.
Mau nghidn;. m cudi eung bao gdm 42 thdng bao mua lai CO phidu cua 37 edng ty dugc nidm yet trdn UBCK Nha nude.
Phuong phap ngiiidn euu su kidn dugc sii dyng hong bai nghien ciiu dd do ludng Igi nhuan bat thudng (Abnormal Return — AR) theo md hinh thj hudng (market model), lgi nhudn bdt thudng tich lOy (Cumulative Abnormal Retum — CAR) cfla cdc doanh nghiep cd hoat ddng mua Igi c6 phieu xung quanh hai su kidn: ngay doanh nghiep ket thfle vide mua lai ed phieu va ngay doanh nghiep thdng bdo kd't qud mua lai ed phidu. Ngay sg kien dugc xac djnh la t = 0, dugc xae djnh trong 2 trudng hgp: (1) la ngdy doanh nghidp kdt thue thuc hien mua lai ed phidu va (2) la ngay doanh nghiep thdng bao ket qua chuong trinh mua lgi ed phieu.
Nghien eiiu ed dd mgt khoang each la hai muoi (20) ngdy giua khung du bao vd khung su kien trong phuang phdp nghidn ciiu su kien nhdm trdnh rui ro Id thdng tin. Neu doanh nghidp bi Id thdng tin thi beta eua cd phieu sd thay ddi trude khung su kien vi lgi nhuan ky vgng cua ed phidu da bao gdm thdng tin rd n cfla su kien.
phidu) vd ngay edng bd kd't qua giao dich mua lai cd phieu (bude 7 hong quy trinh mua lai ed phidu). Vi vdy, nghien eiiu nay khdng chi danh gid tdc ddng cfla su kien doanh nghiep kdt thflc mua lgi cd phieu ddn gia cd phidu efla doanh nghiep ma edn danh gid phdn ling till trudng xung quanh thdi diem doanh nghiep edng bd kdt qud giao djeh thuc hien mua lai.
Bang 1. Lgi nhu^n bat Ihufnie ticb lu5> cua cac dcnnh nghiep c6 Luat dqng Mua lai CO phien ti'CD thi tnwmg chimg khoan Viet Nam, 2008 - 2019
KhDDg s^ ki^n END (-10,10) Kilm djnh t END (-5,5) KiSni dinh i END (-3,3) Kiem dinh t END (-1.1) Kiemdmht END (-3,-1) Kjem djoh t END (1.31 Kiem djnh t
CAR -0.023 (-0.819) 0.012 (0.884) 0 005 (0,408) -0.007 (-1,312"]
0,003 (0023) 0,002 {0,3S2)
* va ** tiicrag mjng Vffi mik y nglala thong ke 10% v a 5 %
Bang 1 md td lgi nhuan bat thudng tieh luy cfla ede ehuong tnnh mua lai cd phidu trong nganh cdng nghiep tai Viet Nam hong giai doan 2015 — 2019. Lgi nhudn bdt thudng tich IQy duge tinh todn hong cdc khung su kidn (-10, 10), (-5, 5), (-3, 3), (-1, 1), (-3, -1) va (I, 3) xung quanh 2 ngdy: ngdy kdt thue vide mua lgi cd phidu vd ngdy thdng bdo ket qua mua lai ed phidu sii dgng md hinh thi trudng. Ddi vdi ngdy doanh nghiep kd't thuc vide mua lai ed phidu (END), ngay 0 la ngay eudi cung trong thdi gian thgc hidn ehuong trinh mua lai.
Bang 1 cho thdy tai khung trude khi xdy ra su kien (-10,10) xung quanh ngay xdy ra su kidn, lgi nhudn bdt thudng cd xu hudng gidm 2,3%. Trong ngdy xdy ra su kidn, lgi nhudn bat thudng cung gidm 0,7%. Chi sau khi su kien xdy ra dugc 3 ngay (1,3) thi lgi nhuan bat thudng mdi cd ddu hieu tang Id 0,2%. Tfl bang kdt qua tren eho thdy cde nhd dau tu hau nhu khdng quan tam hay mdt nidm tin tu ede thdng bdo tdi chinh tir doanh nghiep tdi tiii hudng va doanh nghidp chi dang phdt tin iUeu gia tdi tiii trudng. iChi doanh nghiep cd tin hidu mua lai cd phieu eua doanh nghidp minh ehi la
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( T H A N G a / za.phuang tien dd giflp doanh nghidp phdt tin hieu gid nham tdng gid ed phidu.
Cdc ngiiien ciiu trude ddy hdn the gidi ddu chi ra phdn ling gid cd phidu tich cue ddi vdi ede thdng bdo mua lai c6 phidu cOng nhu ngay doanh nghidp mua lai cd phidu nhu Masulis (1980), Dan (1981), Vemiaelen (1981), Hatakeda vd Isagawa (2004), Chan vd cdc cdng sg (2004), Cesari va edng su (2012), Ben-Rephael vd cdng su (2013) vd Andriosopoulos va L^sfer (2015).
Tuy nhidn, tai Vidt Nam, nghien ciiu lai phdn tich nhflng dnh hudng cfla mua lgi cd phidu xung quanh ngay doanh nghiep kdt thflc viec thuc hien mua lai cd piiidu vd ngay cdng bd kdt qud giao dich mua lai cd phidu. Ket qua tu bdng 4.7 ddi vdi toan bd mdu quan sat eho thdy su khac biei so vdi nhung nghidn ciiu trude, trong dd ddu chi ra eae doanh ngiiiep hdu nhu khdng xudt liien loi nhudn bdt thudng tich luy cd y ngiiia thdng kd xung quanh cd 2 ngdy: ngdy doanh ngiiiep ket thuc thue hien mua lai ed phidu vd ngay doanh nghiep thdng bao ket qud mua lai cd phie'u ngogi trfl cd sg tdng gia cd phidu trude thdi didm doanh nghiep kdt thiie mua lgi cd phidu. Didu nay cd nghia rdng gia ed phidu hau nhu khdng cd phdn ling vdi cd hai su kien: doanh nghiep kdt thue vide thue hidn mua lgi c6 phldu hay doanh nghiep thdng bdo kdt qud mua lai cd phidu. Nguydn nhdn eua hidn tugng ndy cd thd id: Mae du thdng bdo mua lai cd phieu khdng dugc cdng khai nhung tii thdi didm doanh nghidp ldn kd hogch mua lgi cho tdi khi doanh nghiep thue hi$n mua lai c6 phieu ed thd ed su rd ri thdng tin nen mdi cd su phdn ling nhe vd gid ed phieu ngay hudc thdi didm cac cdng ty cdng nghidp kdt thflc mua lai cd phieu. Cd thd ndi cac van ban phdp lu^t Viet Nam edn niueu 16 hdng dan ddn viee qudn ly eung nhu dp dyng eae quy djnh efla phdp ludt cdn ydu vd cd nhidu thidu sdt. Do dd, cac doanh nghidp thudng phat nhung tin hidu gid hoac sai idch tdi thj trudng thdng qua ede hoat ddng khae nhau, dae bidt vdi cac chuong trinh mua lai ed phieu nhdm thao tflng gia eo phldu va xuat hien hidn tinmg rd ri thdng tin. VI vay, cdc nhd ddu tu dudng nhu khdng cdn su tin tudng vdi eac thdng bdo tdi chinh cfla doanh nghiep niem ydt va nhung tin hidu hong cdc ehuong trinh ndy khdng cd may y nghia thuydt phye vdi nhd ddu tu.
4. Ket iuan
Kdt qud kidm dinh tu phuong phdp nghidn ciiu su kidn vd kiem djnh t-test cho thdy hdu nhu ede khung su kl^n xung quanh hoat ddng mua lai ed phidu tgi cdc cdng ty edng nghidp niem ydt tai Yi^t Nam giai dogn 2008-2019 ddu khdng thay xudt hien lgi nhuan bdt thudng tich Ifly — chi sd do ludng bidn ddng gid ed phidu, ngogi tru kdt qud gid cd phidu eua doanh nghiep tiidng bdo mua lai c6 phidu se tang ldn trong khung (-3, -1) trude ngdy doanh nghidp ket thfle viec mua Igi cd phieu. Kdt qua nay hodn todn khdc bidt so
vdi cdc nghien ciiu trude tren thd gidi nhu Ikenberry va cdng su (1995), Liu vd Ziebart (1997), Hatakeda vd Isagawa (2004), Liao va edng sg (2005), MeNally va cdng su (2006) khi chi ra rang cdc thdng bdo mua lai cd phldu ddu lam tang gia ed phidu va eflng khdng ed sg tuong ddng vdi nghidn eiiu efla Vd Xudn Vinh vd Tnnh Tdn Lue (2015) trdn cde edng ty phi tdi chinh Vidt Nam tii nam 2008 den nam 2014 khi nhdm tac gia ket lu^n thi trudng ed phan flng vdi hoat ddng mua lgi cd phidu nhung phdn ling cham.
Tii nhiing ket qua nghidn ciiu tren, ed thd dua ra dugc nhflng hgn ehe gidi thieh cho nhiing ket qud nay.
Thu nhdt, thdng tin vd ngay edng bd ke hoach mua lgi eo phidu tren thgc td khdng dugc cdng khai theo dung quy djnh ndn cd the dan dd'n tinh trgng rd ri thdng tin tmdc khi doanh nghiep thue hien mua lai cd phidu.
Thfl hai, cac thdng bao mua lai ed phieu cua cdc cdng ty nidm yet hen TTCK Viet Nam giai dogn 2008-2018 deu dugc thue hien theo iilnh thiic mua Igi cd phldu hen thi trudng md nen khdng rang bude trdch nhiem phai hoan thanh dflng nhu kd hogch cdng bd ban ddu.
Ben canh dd, mae dfl da ed van bdn phap ludt d^ cap ddn vdn dd nay nhung vdn edn Idng leo ndn cac doanh nghiep dudng nhu khdng cd y djnh hoan thanh vide mua lai 100% nhu da thdng bao tii trude./.
Tai lieu tham i(hao
Ronald V^.Masulis, 2004, Stock Repurchase by Tnder Offer: An Analysis of the Causes of Common Stock Price Changes, The Journal of Finance, VoI.35,N0.2
Larry Y.Dann, 1981, Common stock repurchases:
An analysis of retums to bondholders ans stockhold- ers, Joumal of Financial Economic, Vol.9, Issue 2, Pages 113-138
Gustavo Gmllon and Roni Michaely, 2004, The Information Content of Share Repurchase Programs, The Joumal of Financial, VoI.Lbt, No.2
Trinh Thi Minh Hoa, 2015, Phan flng cfla gid ed phidu ddi vdi thdng bao mua lai cd phan efla cac doanh nghiep: Bdng chung tai Viet Nam
Vd Xuan Vinh, 2014, Nghien cuu lai nhuan bdt thudng khi xudt hien khoi lugng giao djch bdt thudng trdn thi tnrdng chiing khoan Viet Nam, Phdt tridn Kinh te.