A PSR protects the interests of the shareholders of a company that increases its capital. This right is attached to each existing share and entitles its holder to subscribe to new shares during the subscription period so that the holder can retain the percentage he owns in the capital and not suffer a dilution resulting from the rights issue. To take part in a rights issue with maintained preferential subscription rights, new investors must first acquire preferential subscription rights from existing shareholders.
PSRs are listed and transferable up until two days before the end of the rights issue subscription period. At the end of the subscription period, all PSRs that not have been exercised become void and lose their value.