The EC (EU) Procurement Directive 2004/18/EC defines written and in writing broadly in Article 1.12, including electronic means:
12. ‘Written’ or ‘in writing’ means any expression consisting of words or figures which can be read, reproduced and subsequently communicated. It may include information which is transmitted and stored by electronic means.
Public works contracts, public supply contracts and public service contracts – public contracts – must be concluded in writing. This is one of the essential characteristics according to Article 1.2(a) of the Procurement Directive, also called the Classic Directive:
2. (a) ‘Public contracts’ are contracts for pecuniary interest concluded in writing between one or more economic operators and one or more contracting authorities and having as their object the execution of works, the supply of products or the provision of services within the meaning of this Directive.
The written form does not apply only to the final contract, but the main stages such as invitations to tender and tenders have to be in writing and the main stages of the procurement process documented.
The contracting authorities act under public law and the remedies on offer require documentation.