Sorry to bump this old thread, but this afternoon I was in AMS and wanted to use the Crown lounge on arrival. I was traveling economy on an AZ operated, AZ ticketed flight (which is also a KL codeshare). My boarding pass was printed in LIN, and only mentioned the AZ flight number.

I have been denied access to the lounge, after two dragons looked into the terms. They said that I would have had access:
1) if I were flying in business class.
2) if I were flying on KL (not sure whether ticket or metal).
3) if I were flying AZ as I was, but had a Club Freccia Alata card (as opposed to my FB gold).

They were adamant, and I figured that it was not worth arguing--I could kill my time in the Thalys lounge instead.

I could not find any specific set of rules for lounge access on arrival from KLM, but as KLflyerRalph wrote above, the ones on the AF website contradict the (quite specific) rules that the dragons mentioned. (see http://www.airfrance.com/GR/en/commo..._airfrance.htm )

I am a bit confused, because the dragons had no reason to just make up such an intricated set of rules, in place of the much simpler "any skyteam flight" stated on the AF webpage. So which are the rules?