Common shares are the most usual type of shares in a limited company. They normally carry full voting rights and a right to dividends after any preference shares have received their part.
If a company has only one share class, all shares are in practice common shares. When the company raises capital, new classes such as preference shares can be created with different terms. The classes are set out in the articles of association and must be entered in the share ledger.

A B-share is a share class that usually carries lower voting power than the company's A-shares, often a tenth.
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An A-share is a share class that usually carries more votes per share than the company's other shares.
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Preference shares are a share class that gives priority to dividends over other shares.
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Share class refers to different types of shares in a company, e.g. A and B shares, with different rights.
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