Claims

Is "claims" in the following sentence a verb and is Winkin the one who claims? Because, "claims" is present while the other verb referring to Witkin, that is "located", is a past one.

Text:

From the historical narrative provided by classical theory, Witkin located Manet’s work in the transition between traditional and modern society and claims that one can uncover not only a more or less conscious attempt by the artist to shock his contemporaries with his choice of subject matter and manner of representation, but also the emergence of a more “abstract,” subject-oriented style that would characterize modernism and modern social relations.