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system
is there any reason to buy shares before/after a split?
user
there has been a lot of research on the effects of stock splits. some studies have concluded that: however note that (i) these are averages over large samples and does not say it will work on every split and (ii) most of the research is a bit dated and more recent papers have often struggled to find any significant performance impact after 1990, possibly because the effect has been well documented and the arbitrage no longer exists. this document summarises the existing research on the subject although it seems to miss some of the more recent papers. more practically, if you pay a commission per share, you will pay more commissions after the split than before. bottom line: don't overthink it and focus on other criteria to decide when/whether to invest.
assistant