Art. 20 Multiple liability If a creditor has a claim against several debtors who are liable for the same claim, and one of the debtors has already satisfied the claim in whole or in part, the question of that debtor's right to demand compensation from the other debtors shall be governed by the law applicable to that debtor's non-contractual obligation towards the creditor.
Art. 21 Formal validity A unilateral act intended to have legal effect and relating to a non-contractual obligation shall be formally valid if it satisfies the formal requirements of the law governing the non-contractual obligation in question or the law of the country in which the act is performed.
Art. 22 Burden of proof 1. The law governing a non-contractual obligation under this Regulation shall apply to the extent that, in matters of non-contractual obligations, it contains rules which raise presumptions of law or determine the burden of proof.
2. Acts intended to have legal effect may be proved by any mode of proof recognised by the law of the forum or by any of the laws referred to in Article 21 under which that act is formally valid, provided that such mode of proof can be administered by the forum.

CHAPTER VI. OTHER PROVISIONS

Art. 23 Habitual residence 1. For the purposes of this Regulation, the habitual residence of companies and other bodies, corporate or unincorporated, shall be the place of central administration.Where the event giving rise to the damage occurs, or the damage arises, in the course of operation of a branch, agency or any other establishment, the place where the branch, agency or any other establishment is located shall be treated as the place of habitual residence.
2. For the purposes of this Regulation, the habitual residence of a natural person acting in the course of his or her business activity shall be his or her principal place of business.
Art. 24 Exclusion of renvoi The application of the law of any country specified by this Regulation means the application of the rules of law in force in that country other than its rules of private international law.
Art. 25 States with more than one legal system 1. Where a State comprises several territorial units, each of which has its own rules of law in respect of non-contractual obligations, each territorial unit shall be considered as a country for the purposes of identifying the law applicable under this Regulation.
2. A Member State within which different territorial units have their own rules of law in respect of non-contractual obligations shall not be required to apply this Regulation to conflicts solely between the laws of such units.