Where the convicted person is serving several sentences which are not concurrent and all of which carry a security period, these security periods are served cumulatively and continuously.
In the case of concurrent sentences that all include periods of imprisonment, the total period of imprisonment to be served is reduced by a maximum of two-thirds of these sentences after they have been reduced to the legal maximum. If a sentence of life imprisonment has been imposed, the periods of imprisonment shall be served cumulatively up to a maximum of 22 years or, where applicable, up to the maximum period of imprisonment specially set by the Assize Court pursuant to the second paragraph of Article 221-3, the last paragraph of article 221-4 and article 421-7 of the Penal Code.
When the convicted person is serving several sentences with a security period and which have been confused, the length of the security period to be served is that of the longest security period.