A call option (Swedish: köpoption) gives the holder the right but not the obligation to buy a share at a predetermined price, the strike price, within a set period. The issuer must sell if the holder exercises it. The opposite is a put option.
In unlisted companies, call options are often used between owners, for example in a shareholders' agreement or an incentive program. Since they concern existing shares, they differ from warrants. On exercise, the transfer must be entered in the share ledger.

An option gives the holder the right, but not the obligation, to buy or sell an asset at a set price.
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A strike price is the predetermined price per share at which an option entitles the holder to trade.
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A warrant gives the right to subscribe for new shares in a company at a set price.
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An option holder is the person who holds an option and thereby the right to buy or subscribe for shares.
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