Possession (Swedish: besittning) is a legal concept describing that someone actually has an item in their control and can dispose of it. It does not matter whether the holding is rightful or not. Possession is therefore not the same as ownership.
Possession matters when share certificates are used as security. In a pledge of shares with certificates, the certificate normally has to be handed over to the pledgee, known as delivery, for the pledge to obtain third-party protection. The pledge should also be noted in the share ledger.

Third-party protection means that a right to property, such as shares, also applies against third parties.
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A pledge of shares means shares are provided as security for a debt, often a loan.
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A share certificate is written proof that a person owns certain shares in a limited company.
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