The film begins with the New Line Cinema logo and the opening credits say "NEW LINE CINEMA presents a BENDERSPINK production". 
The credits finish with:

COPYRIGHT © MMV Media I! Filmproduktion München GmbH & Co. KG
™NEW LINE PRODUCTIONS, INC.  ALL RIGHTS RESERVED.

In association with  Media I! Filmproduktion München GmbH & Co. KG

A HISTORY OF VIOLENCE
A New Line Cinema Release

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New Line Cinema is US based, as is Benderspink, but Media I! Filmproduktion is German.  The movie was filmed in Canada - is the primary production company New Line Cinema, making the CoO United States?

Benderspink are the production company, but as they are US as well it makes no difference.
New Line are the distributor, hence the "presents" credit.

Quoting wossname:

Quote:
So would Media I! Filmproduktion München GmbH & Co. KG be a studio?  At present the studios assigned to that profile are New Line, Benderspink and Entertainment in Video (I presume as distributors).

I may be wrong, but the way that they are credited hints that it's more of a funding situation in their case than any hands-on production.
If I'm remembering rightly Germany has very good tax benefits for films that are produced or co-produced by German companies. A lot of American studios have cottoned on to this and you'll find quite a few Hollywood films will have a German production company involved.

Edit: it's interesting to note that History of Violence is the only film this company seems to have produced...  I could say more but lawyers may get involved! 

Quoting DJ Doena:

Quote:
forget it, i confused NLC with WingNut

Strange, it's usually only Americans who do that! 

Quoting wossname:

Quote:
(...)
"NEW LINE CINEMA presents a BENDERSPINK production".
(...)

New Line Cinema is US based, as is Benderspink, but Media I! Filmproduktion is German.  The movie was filmed in Canada - is the primary production company New Line Cinema, making the CoO United States?

No, "New Line Cinema" is not the primary production company, it's the theatrical distribution company. The primary production company is Benderspink. So the end result is the same, the CoO is US.

Quoting RHo:

Quote:
Quoting Peter von Frosta:

Quote:
The copyright is with a german company, the actual rights belong to a german company. Since we argumented this way with the Lord of the Rings, this is a german movie (and the Bourne movies as well, but it won't get accepted).

We have never argued that the copyright holder defines the primary production company! It has always been the company which has done the actual production, except that Gerry once called Lord of the Rings US by mistake (which has been corrected to New Zealand afterwards)

Then Benderspink it is