Have many not-for-profit scholarly publishers joined the private sector? If so, has anyone checked their tax status lately?

The Association of American Publishers (AAP) Applaud the “Research Works Act,” Bipartisan Legislation To End  Government Mandates on Private-Sector Scholarly Publishing - details here: http://publishers.org/press/56/

This is an awful bill, which would prevent the U.S. government from requiring public access to research funded by the U.S. public. For details and action steps, see the Alliance for Taxpayer Access site. 

Among the members of the AAP are many traditional not-for-profit publishers, such as scholarly societies and university presses. If they are now claiming, through AAP, to be private-sector publishers, does this mean their not-for-profit status has changed? If so, has anyone checked their tax status lately?

Yet another reason for such publishers to denounce the AAP's stand and distance themselves from AAP until such time as AAP  stops supporting this move against the public interest.

 This post is public domain to open access advocates.