What documentation should each member of a UTE contribute?
Ok, let's put a little life to this, because the official explanation is denser than a Sunday afternoon without wifi.
A UTE, or temporary union of companies, is basically like when several colleagues decide to join to mount something big, but to the beast and with legal paperwork in between. It serves so that several companies can go for a public contract that, by themselves, or joke could catch. Of course, to launch to the pool, each company has to present a mogollón of papers that prove that they are not mindland and that they can really with the brown.
What to present? It depends on the country, on the agency and, sometimes, on the humor of the official on duty. But, in general, prepare to release the typical:
The Minutes of Constitution of the UTE: Here we have to put the data of all the companies involved, how much each one puts and, eye, commit to eating the brown together if the thing comes out. You also have to choose a representative (the pringeado of trust) that all the efforts will be eaten until the UTE is dissolved.
Papers demonstrate that each company exists and can legally operate: deeds, statutes, CIF, registration in the Mercantile Registry ... the classic combo, come on.
Tests that they are not pelaos: annual accounts, audits, some document where they say "look, we have money for this", etc.
Documents that teach that they know what they do: certificates of previous works, quality stamps, curriculum of the technical personnel, description of the facilities, studies, whatever demonstrates that they are not fans.
A statement swearing that they are not involved in any mess that prevents them from hiring with the administration. That is, they are not vetoed or have pending moves.
All this has to be original or, if they are copies, that are well legalized. And if any role is in another language, then to go through the official translator, who do not walk nonsense.
By the way, do not sleep reading the tender specifications: sometimes they ask for strange things according to the contract. Better check everything before they catch you offside.
And, to finish off, although it is set up a bomb to distribute risks and resources, it also means that if the thing goes wrong, everyone pays the duck. So better to be clear where you get before throwing yourself into the adventure. Don't say I didn't let it know.