On April 3, 2011, Callahan published an op-ed in the ''New York Times'' entitled "Bringing Donors out of the Shadows" about politically-motivated philanthropy. The piece was critical of the practice, on "both the left and the right," of channeling funds anonymously through 501(c)3 and (4) nonprofit groups in order to advance their political views. Callahan singled out the brothers [[David H. Koch]] and [[Charles G. Koch]] as an example of donors who conceal "the recipients of their largess, even as they get to write it off on their taxes."<ref>{{cite web|last=Callahan|first=David|title=Bringing the Donors out of the Shadows|url=http://www.nytimes.com/2011/04/04/opinion/04Callahan.html|work=New York Times|publisher=New York Times}}</ref> According to their website, however, [[Koch Industries]] challenged many of the claims made by Callahan in a letter to the editor.<ref>{{cite web|title=We Ask The New York Times to Correct David Callahan’s Op-Ed Article|url=http://www.kochfacts.com/kf/we-ask-the-new-york-times-to-correct-david-callahans-op-ed-article/|work=Koch Industries|publisher=Koch Industries|accessdate=28 April 2011}}</ref> On April 14, 2011, the ''New York Times'' printed a correction acknowledging one imprecision in Callahan's piece, which is that the Koch brothers say they do not provide financial support to [[FreedomWorks]], a conservative group which originated from the Koch-funded [[Citizens for a Sound Economy]].<ref>{{cite web|last=Callahan|first=David|title=Bringing the Donors out of the Shadows|url=http://www.nytimes.com/2011/04/04/opinion/04Callahan.html|work=New York Times|publisher=New York Times}}</ref>
