On August 18, the New York Stock Exchange (NYSE) issued a proposed amendment to Section 202.06 of the NYSE Listed Company Manual, which would prohibit the issuance of material news by a listed company between the official closing time of the NYSE’s trading session until the earlier of the publication of such company’s official closing price or five minutes after the NYSE’s official closing time. In explaining the purpose of the proposed amendment, the NYSE noted that, because trading can occur after 4:00 p.m. ET (the NYSE’s official closing time) on other markets “if a listed company released material news immediately after 4:00 p.m., but before the closing auction on the NYSE is completed, there can be a significant price difference in nearly contemporaneous trades on other markets and the closing price on the [NYSE].”

The full text of the proposed amendment is available here.