18 U.S. Code § 2257 – Record keeping requirements
(a) Whoever produces any book, magazine, periodical, film, videotape, digital image, digitally- or computer-manipulated image of an actual human being, picture, or other matter which—
(b) Any person to whom subsection (a) applies shall, with respect to every performer portrayed in a visual depiction of actual sexually explicit conduct—
(4) for any person knowingly to sell or otherwise transfer, or offer for sale or transfer, any book, magazine, periodical, film, video, or other matter, produce in whole or in part with materials which have been mailed or shipped in interstate or foreign commerce or which is intended for shipment in interstate or foreign commerce, which—
(2) the term “produces”—
(B) does not include activities that are limited to—