For the film "Unknown" (2011), country of origin should be USA / France / United Kingdom, based on the film's text credits for locality Australia, as follows:

Film run time = 01:53:11 (113 mins).

Opening credits at 00:00:31 displayed the following title pages:
______________________________________
    WARNER BROS. PICTURES PRESENTS
.....................................................................................
IN ASSOCIATION WITH DARK CASTLE ENTERTAINMENT      <== this is USA, formed by producer Joel
                                                                                              Silver and others in 1999.
.....................................................................................
              A PANDA PRODUCTION                                        <== this is USA, "Panda Productions, Inc."
                                                                                                formed by producer Leonard Goldstein
_______________________________________                            in 1984.


End credits at 01:49:27 displayed:
_______________________________
FINANCED IN ASSOCIATION WITH
          STUDIOCANAL                                                          <== this is France

          PRODUCED AT
    STUDIO BABELSBERG
_______________________________


End credits at 01:52:38 displayed:
____________________________________________
    A UK / GERMANY / FRANCE CO-PRODUCTION

                  HORTICUS UK LTD                                          <== this is U.K.
      ZWÖLFTE BABELSBERG FILM GmbH                              <== this is Germany
                  STUDIOCANAL S.A.                                          <== this is France.
      DEUTERSCHER FILMFORDERFÖNDS (DFFF)                    <== this is Germany.
  MEDIENBOARD BERLIN-BRANDENBURG GmbH                    <== this is Germany.
___________________________________________

Film's copyright at 01:52:49 displayed:
______________________________________
    © 2011 DARK CASTLE HOLDINGS, LLC                    <== this is USA (refer
          ALL RIGHTS RESERVED                                            https://uspto.report/copyright/24702898) for                               
______________________________________                      confirmation.

End credits at 01:53:06 displayed:
__________________________
        Distributed by
WARNER BROS. PICTURES
__________________________

Not that it makes any difference here, but I'm not entirely convinced that "presents in association with Dark Castle Entertainment" should be considered as far as the film's CoO is concerned. The contribution rules on the CoO tell us to look at where the film's "production company/companies are based", not the theatrical release studio(s). That's why ObiKen correctly ignores Warner Bros. Pictures.

But the opening credits state: "A presents, in association with B, a C production". There's no doubt that company A should be ignored as far as the CoO is concerned, but isn't company B still part of the "presents" section, too? Rather than being part of the "production" section? To me, it seems that the "production" section only starts from Panda onwards.

Note that the Wikipedia-page for Dark Castle Entertainment includes phrases like "Dark Castle Entertainment originally acquired the US rights to The Loft [...] with the intention of releasing the film through Warner Bros." I can't help thinking that "acquiring the US rights" to a film doesn't automatically make Dark Castle a production company of that particular film. Looking through the films Dark Castle's associated with, it seems there are films where Dark Castle actually served as the production company, like 'Gothika', and film's where they merely "acquired the US rights". They way in which they're credited in those two scenario's is distinctively different:

- in films where Dark Castle is actually a production company, like 'Gothika', the opening credits state: "Warner Bros. Pictures and Columbia Pictures present a Dark Castle Entertainment production" - no ambiguity there;

- but in films where Dark Castle merely "acquired the US rights", like 'Unknown' or 'Splice, the opening credits state: "Warner Bros. Pictures presents, in association with Dark Castle Entertainment, a Copperheart Entertainment production" (for 'Splice') or "Warner Bros. Pictures presents, in association with Dark Castle Entertainment, a Panda production" (for 'Unknown').

This seems to be applied in a pretty consistent manner. Again, this makes no difference to 'Unknown', as Panda is a US company, too. But this is something that affects many films - do we treat "company B" in "A presents, in association with B, a C production" as part of the "presents" section, or as part of the "production" section"? Should we treat "A presents, in association with B, a C production" different than "A presents a B/C production" different than "A presents a B/C production"? Or not?