If your account has been approved for trading fractions and a US, Canadian or European corporate action issues fractional shares, the fractional shares will remain in your account. However, if your account does not have permissions to trade in fractions or the corporate action is issuing non-eligible shares, the fractional shares will be liquidated.
Please be aware that Interactive Brokers (IBKR) holds all positions in street name. As such, corporate actions which may include a round up privilege whereby a broker may request that each holder of a fractional position be rounded up will not be supported by IBKR.
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