(1) An undertaking that -

(a) enters into, or implements, an agreement,

(b) makes or implements a decision, or

(c) engages in a concerted practice,

that is prohibited by section 4(1) or by Article 101(1) of the Treaty on the Functioning of the European Union, and that -

(i) intentionally or recklessly acts to prevent, restrict or distort competition, or

(ii) intentionally or recklessly makes omissions having the effect of preventing, restricting or distorting competition,

shall be guilty of an offence.

(2) In proceedings for an offence under subsection (1), it shall be presumed that an agreement between competing undertakings, a decision made by an association of competing undertakings or a concerted practice engaged in by competing undertakings the purpose of which is to -

(a) directly or indirectly fix prices with respect to the provision of goods or services to persons not party to the agreement, decision or concerted practice,

(b) limit output or sales,

(c) share markets or customers, or