Political information—particularly political advertising—has been at the heart of American campaigns and elections for more than a century. Throughout the last century, candidates, parties, and interest groups have competed to make their case to voters in the hopes of winning elections and shaping policy debates. At the same time, Congress, regulatory agencies, and the courts have wrestled with how much, and what kind, of information should be available to the public about the sources of those political messages. Questions have also emerged about whether certain actors, such as corporations and unions, should be permitted to participate in elections and other political debates to the same extent as voters. Modern campaign finance policy and law, which emerged in the 1970s, but which built on reforms first pursued in the early 1900s, has responded with a combination of provisions designed to restrict the amounts and sources of funds in federal elections on one hand, and documenting the sources and amounts of funds that are permitted on the other. Political advertising has both enabled the public to become more informed about campaigns and policy contests, and, perhaps, made it more challenging for the electorate and policymakers to keep track of the various players and issues involved in political debates. This has been particularly true since the 1960s, when broadcast political advertising first became prominent, political professionals began to specialize in media production, and the electorate increasingly turned to television for information. The latest iteration of the debate over which corporations, unions, and other groups should be permitted to spend funds on political ads, and how so, was renewed on January 21, 2010, when the U.S. Supreme Court issued its highly anticipated decision in Citizens United v. Federal Election Commission (FEC) . The DISCLOSE Act, "Democracy is Strengthened by Casting Light on Spending in Elections," which the Committee on House Administration reported, as amended, on May 25, 2010, is the most prominent legislative response to Citizens United to date. As with the case itself, the DISCLOSE Act is particularly relevant for the ongoing policy debate surrounding political advertising and its transparency. This report is designed to provide an overview and analysis of (1) major policy issues addressed in Citizens United and the DISCLOSE Act; (2) major provisions of H.R. 5175 , S. 3295 , and S. 3628 compared with current federal campaign finance law, as shown in Table 1 at the end of this report; and (3) selected issues for congressional consideration and potential implications of enacting or not enacting the DISCLOSE Act. Legislative developments surrounding the DISCLOSE Act have generally unfolded quickly since the House and Senate bills were introduced. As such, this report will be updated periodically to reflect recent developments and emerging issues. Citizens United is significant because of its potential to change the ways in which corporations, unions, and tax-exempt organizations participate in American elections. Although restrictions on those actors have evolved over time, corporations, unions, and certain tax-exempt organizations were largely banned from spending treasury funds in federal elections for decades. As a result of Citizens United , these groups are permitted to use general treasury funds to make independent expenditures, which are defined as communications "expressly advocating the election or defeat of a clearly identified candidate" and that are not coordinated with any candidate or party, and electioneering communications, which are defined as broadcast, cable or satellite transmissions that refer to a clearly identified federal candidate, aired within 60 days of a general election or 30 days of a primary. Corporations and unions are still subject to the prohibition on using general treasury funds to make contributions to candidates and political parties. The 1907 Tillman Act, which is considered to be the first major federal campaign finance law, prohibited corporations from making contributions to political parties. With the 1947 Taft-Hartley Act, Congress expanded the prohibition to include corporate contributions to both parties and candidates, as well as expenditures in federal elections. Taft-Hartley also included labor unions in the prohibition. The early prohibitions on corporate and labor union treasury funded contributions and expenditures were included in the first modern federal campaign finance law, the Federal Election Campaign Act of 1971, also known as FECA. The prohibitions are codified at 2 U.S.C. § 441b. In an exception to the prohibition on corporate and union treasury spending, FECA allows for the creation of separate segregated funds or political action committees , also known as PACs . Specifically, corporations and unions can use their treasury funds to establish, operate and solicit voluntary, limited contributions to their PACs. These voluntary PAC donations can then be used to contribute to federal campaigns or to make expenditures that expressly advocate election or defeat of federal candidates. In the 1976 landmark Supreme Court decision, Buckley v. Valeo , the constitutionality of many provisions in FECA was challenged. This case is important because it established the framework for constitutional analysis of campaign finance regulation. In Buckley , the Court upheld reasonable contribution limits, invalidated certain expenditure limits, and upheld reporting and disclosure requirements. In addition, the Court created the distinction between issue advocacy and express advocacy , finding that a communication could be regulated if it contained words express advocacy of the election or defeat of a candidate, which includes words such as "vote for" or "vote against." By contrast, such ads could not be regulated if they only contained general public policy messages that fell short of calling for election or defeat of candidates, sometimes referred to as issue advocacy . A generation would pass between the enactment of FECA and the next time that Congress would again enact major campaign finance legislation—the Bipartisan Campaign Reform Act of 2002 (BCRA)—but political advertising and the funding sources for that advertising remained prominent during both legislative debates. As the legislation that became BCRA was being debated in the late 1990s and early 2000s, a chief concern surrounding issue advocacy was whether the ads were actually about public policy issues—as proponents of the advertisements suggested—or whether they were really messages designed to encourage votes for or against candidates within in the context of ads that were only nominally related to public policy. In an effort to restrict issue advocacy, BCRA created a new concept within FECA known as electioneering communications in order to regulate messages that might affect elections, but did not expressly advocate for the election or defeat of a clearly identified federal candidate. Importantly, BCRA prohibited corporations and unions from using general treasury funds to pay for electioneering communications, meaning that potentially any ad that even mentioned a political candidate during pre-election periods would have to be paid for with PAC funds or not aired. In 2007, in FEC v. Wisconsin Right to Life, Inc., the Supreme Court limited the application of the prohibition, thereby easing some restrictions on corporate- and union-funded ads that would otherwise be classified as electioneering communications. As a result of the Court's ruling, if an advertisement could reasonably be interpreted as something other than calling for a vote for or against a candidate, it could not be prohibited. While this ruling limited the application of the electioneering communication prohibition, it did not expressly overrule it. Citizens United, a corporation exempt from taxes under Internal Revenue Code (IRC) § 501(c)(4), produced a documentary about a presidential candidate, then-Senator Hillary Clinton. The group released the film in theaters and on DVD, and planned to make it available through video-on-demand and to fund broadcast and cable television advertisements promoting the movie. In Citizens United v. Federal Election Commission (FEC), the U.S. Supreme Court considered to what extent the organization was subject to the federal prohibitions on corporate treasury funding of independent expenditures, electioneering communications, and related reporting requirements. On January 21, 2010, the Supreme Court issued its long-awaited ruling in this case, and invalidated the prohibition on corporations and labor unions using their general treasury funds to make independent expenditures and electioneering communications. The Court determined that these prohibitions constitute a "ban on speech" in violation of the First Amendment. In so doing, the Court also overturned its 1990 ruling in Austin v. Michigan Chamber of Commerce , which had upheld restrictions on corporate-funded independent expenditures, finding that it provided no basis for allowing the government to limit such independent expenditures. The Court also overturned the portion of its decision in McConnell v. FEC upholding the facial validity of the prohibition on electioneering communications in BCRA, finding that the McConnell Court relied on Austin. The Court in Citizens United , however, upheld the disclaimer (which is sponsor information included within a communication) and disclosure requirements for electioneering communications as applied to the documentary. These requirements, the Court held, could be applied to the film and related advertisements that Citizens United had produced. According to the Court, while they may burden the ability to speak, disclaimer and disclosure requirements "impose no ceiling on campaign-related activities." It does not appear that the Court's ruling in Citizens United affects the validity of Title I of BCRA, which generally bans the raising of unregulated, also known as "soft," money by national parties and federal candidates or officials, and restricts soft money spending by state parties for "federal election activities." Furthermore, Citizens United does not appear to affect the ban on corporate or union contributions to political candidates. As a consequence of Citizens United , federal campaign finance law does not limit corporate and labor union treasury funding for independent expenditures and electioneering communications. Corporations and unions may still establish PACs, but are only required to use PAC funds in order to make contributions to candidates, parties, and other political committees. Given these developments, questions have emerged about how political advertising might be affected by the Court's decision in Citizens United and whether the airwaves will be flooded with corporate and labor union express advocacy.