A share certificate is a document showing that a specific shareholder owns certain shares in a limited company. It serves as proof of ownership and states which share numbers it covers. In private companies a certificate is issued only if a shareholder requests one.
A certificate does not replace the share ledger — the ledger is the official record of ownership. It notes which certificates have been issued and to whom. When shares change hands through a transfer of shares, the certificate must also be handled correctly.

A share ledger is a record of a company's shares and who its shareholders are.
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A share is a unit of ownership in a limited company that gives the right to vote and to receive dividends.
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A share number is the sequential number that each individual share in a company has.
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A shareholder is a person or company that owns one or more shares in a limited company.
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