The effect of share repurchase programs' announcements on firms' market values

In this study, it is aimed to examine whether the data regarding the announcements regarding the launch of the share buyback program announced to the public in Turkey, Greece and Poland affect the share returns in the short term and whether the relevant share markets are efficient in semi-strong form within the scope of the Efficient Markets Hypothesis and with the event study method. In the study, announcements regarding share buyback programs made public in Turkey, Greece and Poland during the 4-year period between 01.01.2020 and 31.12.2023 were discussed. The findings showed that Turkish and Polish stock markets were not effective in semi-strong form at 5% and 10% significance levels in terms of their reactions to the announcements about the launch of the share buyback program announced to the public. On the other hand, it has been revealed that the Greek share market is effective in the semi-strong form at all 1%, 5% and 10% significance levels in terms of its reactions to the announcements about the launch of the share buyback program announced to the public. In the study, the reactions of each country to the public announcements regarding the launch of the share buyback program were also analyzed on a sectoral basis and according to asset size.