Attested Publishing is a trustworthy accreditation, by electronic signature and timestamping, of the moment of beginning of the public diffusion of the information in the "Contracting Profile". The European Union is updating the rules concerning procurement procedures for public contracts thanks to the Directives 2004/18/EC and 2004/17/EC. These Directives introduce a new procedure which develops electronic procedures. The new procedure is based on the principles of simplification, harmonization and modernization. According to the new public procurement, the electronic communication will have the same validity that the traditional communication. For this reason, these Directives leave market operators free to choose the mean of communication to use in their procedures. In relation with this regulation, Article 175 b) of Spanish Law 30/2007 states the regulation of new electronic systems such as electronic auction and dynamic acquisition system. Considering these legal aspects, Public Administration has created the "Contracting Profile", a web in which the information relative to the administrative contracts (calendar bid, provisional adjudications…) is published. "Contracting Profile" should guarantee in a reliable way the date of the publication of procedures of public service contracts . In relation with the requirements of "Contracting Profile", EADTrust offers services of timestamping and electronic signature in order to provide certainty to certain times of the procedure of public service contracts and to reinforce the juridical validity of administrative documents published. EADTrust’s services of timestamping and electronic signature allow identifying the author, the integrity of the data, as well as, the date of the signed.