"The United States Code is the official codification of the general and permanent laws of the United States of America. The Code was first published in 1926, and a new edition of the code has been published every six years since 1934. The 2012 edition of the Code incorporates laws enacted through the One Hundred Twelfth Congress, Second Session, the last of which was signed by the President on January 15, 2013. It does not include laws of the One Hundred Thirteenth Congress, First Session, enacted between January 2, 2013, the date it convened, and January 15, 2013. By statutory authority this edition may be cited "U.S.C. 2012 ed." As adopted in 1926, the Code established prima facie the general and permanent laws of the United States. The underlying statutes reprinted in the Code remained in effect and controlled over the Code in case of any discrepancy. In 1947, Congress began enacting individual titles of the Code into positive law. When a title is enacted into positive law, the underlying statutes are repealed and the title then becomes legal evidence of the law. Currently, 26 of the 51 titles in the Code have been so enacted. These are identified in the table of titles near the beginning of each volume. The Law Revision Counsel of the House of Representatives continues to prepare legislation pursuant to 2 U.S.C. 285b to enact the remainder of the Code, on a title-by-title basis, into positive law. The 2012 edition of the Code was prepared and published under the supervision of Ralph V. Seep, Law Revision Counsel. Grateful acknowledgment is made of the contributions by all who helped in this work, particularly the staffs of the Office of the Law Revision Counsel and the Government Printing Office"--Preface.

JCS-5-05. Joint Committee Print. Provides an explanation of tax legislation enacted in the 108th Congress. Arranged in chronological order by the date each piece of legislation was signed into law. This document, prepared by the staff of the Joint Committee on Taxation in consultation with the staffs of the House Committee on Ways and Means and the Senate Committee on Finance, provides an explanation of tax legislation enacted in the 108th Congress. The explanation follows the chronological order of the tax legislation as signed into law. For each provision, the document includes a description of present law, explanation of the provision, and effective date. Present law describes the law in effect immediately prior to enactment. It does not reflect changes to the law made by the provision or subsequent to the enactment of the provision. For many provisions, the reasons for change are also included. In some instances, provisions included in legislation enacted in the 108th Congress were not reported out of committee before enactment. For example, in some cases, the provisions enacted were included in bills that went directly to the House and Senate floors. As a result, the legislative history of such provisions does not include the reasons for change normally included in a committee report. In the case of such provisions, no reasons for change are included with the explanation of the provision in this document. In some cases, there is no legislative history for enacted provisions. For such provisions, this document includes a description of present law, explanation of the provision, and effective date, as prepared by the staff of the Joint Committee on Taxation. In some cases, contemporaneous technical explanations of certain bills were prepared and published by the staff of the Joint Committee. In those cases, this document follows the technical explanations. Section references are to the Internal Revenue Code unless otherwise indicated.