In trading, the term dual listing is used in reference to stocks which have two separate primary listings on two separate stock exchanges.
A dual listing may occur when a company chooses to list its stock on a stock exchange in another region in in order to reach a different group of investors, while also maintaining its primary listing on the exchange which first listed it.
Dual listings also occur when two companies, each of which has a primary listing on a stock exchange, merge to form a single company. One example of this is Swiss engineering firm ABB which was formed by the merger of Swiss firm Brown, Boveri & Cie. and Swedish firm ASEA. After the merger, the resulting firm maintained primary listings both on what is now the SIX Swiss Exchange and what is now Nasdaq Stockholm.
Typically, dual listings are accomplished by dividing a company into two separate holding companies. For example, a Swiss company may choose to create a U.S. holding company which can hold a primary listing on a U.S. stock exchange in order to attract a broader investment base. Companies which have dual listings are known as dual-listed companies (DLCs), or colloquially as Siamese twins.
Shares in the same company sold on the two different exchanges may differ from each other. For example, the dividends applicable to a company’s shares sold on one primary exchange may differ from those applicable to its shares sold on its other primary exchange. This may occur after a merger, for example, if the shares issued by one of the companies differ from those of the other company. However, this is the exception rather than the rule.
A company may also choose to maintain its primary listing on one exchange while opening a secondary listing on a different exchange, or to move its primary listing to a different exchange while maintaining a secondary listing on its former primary exchange. Neither of these scenarios constitutes a dual listing.
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