One aspect of increased use of the Internet for electronic mail (e-mail) has been the advent of unsolicited advertising, also called "unsolicited commercial e-mail" (UCE), "unsolicited bulk e-mail," "junk e-mail, "or "spam." Complaints often focus on the fact that some spam contains, or has links to, pornography; that much of it is fraudulent; and the volume of spam is steadily increasing. However, recent research shows that Internet users' concerns about spam are actually decreasing, even while the volume of spam continues to increase. For example, in a survey conducted by the Pew Internet & American Life Project during February and March 2007, respondents stated that they were "less bothered by [spam]" now than they reported being in the previous survey, conducted in June 2003. Specifically, in the 2003 survey, 25% of respondents stated that spam was a "big problem"; in the 2007 survey, that figure had dropped to 18%. Even more striking is that the percentage of participants who responded that spam was "not a problem at all" rose from 16% to 28% between 2003 and 2007. The percentage of respondents stating that spam is "an annoyance, but not a big problem" has stayed roughly the same at 57% and 51% in 2003 and 2007, respectively. One reason for this change in attitude towards spam is attributed to Internet users' growing savvy with identifying spam on their own as well as their increased use of spam filters (whether provided by their Internet service provider (ISP) or purchased on their own). In 2007, 71% of Internet users use filters, up from 65% in 2005. One challenge in debating the issue of spam is defining it. To some, it is any commercial e-mail to which the recipient did not "opt-in" by giving prior affirmative consent to receiving it. To others, it is commercial e-mail to which affirmative or implied consent was not given, where implied consent can be defined in various ways (such as whether there is a pre-existing business relationship). Still others view spam as "unwanted" commercial e-mail. Whether or not a particular e-mail is unwanted, of course, varies per recipient. Since senders of UCE do find buyers for some of their products, it can be argued that at least some UCE is reaching interested consumers, and therefore is wanted, and thus is not spam. Consequently, some argue that marketers should be able to send commercial e-mail messages as long as they allow each recipient an opportunity to indicate that future such e-mails are not desired (called "opt-out"). Another group considers spam to be only fraudulent commercial e-mail, and believe that commercial e-mail messages from "legitimate" senders should be permitted. The DMA, for example, considers spam to be only fraudulent UCE. The differences in defining spam add to the complexity of devising legislative or regulatory remedies for it. Some of the bills introduced in the 108 th Congress took the approach of defining commercial e-mail, and permitting such e-mail to be sent to recipients as long as it conformed with certain requirements. Other bills defined unsolicited commercial e-mail and prohibited it from being sent unless it met certain requirements. The final law, the CAN-SPAM Act (see below), took the former approach, defining and allowing marketers to send such e-mail as long as they abide by the terms of the law, such as ensuring that the e-mail does not have fraudulent header information or deceptive subject headings, and includes an opt-out opportunity and other features that proponents argue will allow recipients to take control of their in-boxes. Proponents of the law argue that consumers will benefit because they should see a reduction in fraudulent e-mails. Opponents of the law counter that it legitimizes sending commercial e-mail, and to the extent that consumers do not want to receive such e-mails, the amount of unwanted e-mail actually may increase. If the legislation reduces the amount of fraudulent e-mail, but not the amount of unwanted e-mail, the extent to which it reduces "spam" would depend on what definition of that word is used. On December 16, 2004, the FTC issued its final rule defining the term "commercial electronic mail message," but explicitly declined to define "spam." Tips on avoiding spam are available on the FTC website and from Consumers Union. Consumers may file a complaint about spam with the FTC by visiting the FTC website and choosing "File a Complaint" at the bottom of the page. The offending spam also may be forwarded to the FTC, at spam@uce.gov , to assist the FTC in monitoring spam trends and developments. The September 2004 issue of Consumer Reports has a cover story about spam, including ratings of commercially available spam filters consumers can load onto their computers. Also, individual ISPs use spam filters (though the filters may not catch all spam) and have mechanisms available for subscribers to report spam. Controlling spam is complicated by the fact that some of it originates outside the United States and thus is not subject to U.S. laws or regulations. Spam is a global problem, and a 2001 study by the European Commission concluded that Internet subscribers globally pay 10 billion Euros a year in connection costs to download spam. Some European officials complain that the United States is the source of most spam, and the U.S. decision to adopt an opt-out approach in the CAN-SPAM Act (discussed below) was not helpful. In April 2005, a British anti-spam and anti-virus software developing company, Sophos, listed the United States as the largest spam producing country, exporting 35.7% of spam (down from 42.1% in December 2004); South Korea was second, at 25% (up from 13.4% in December 2004). Tracing the origin of any particular piece of spam can be difficult because some spammers route their messages through other computers (discussed below) that may be located anywhere on the globe. The 108 th Congress passed the CAN-SPAM Act, S. 877 , which merged provisions from several House and Senate bills. Signed into law by President Bush on December 16, 2003 ( P.L. 108-187 ), it went into effect on January 1, 2004. P.L. 108-187 includes the following major provisions. Commercial e-mail may be sent to recipients as long as the message conforms with the following requirements: —transmission information in the header is not false or misleading; —subject headings are not deceptive; —a functioning return e-mail address or comparable mechanism is included to enable recipients to indicate they do not wish to receive future commercial e-mail messages from that sender at the e-mail address where the message was received; —the e-mail is not sent to a recipient by the sender, or anyone acting on behalf of the sender, more than 10 days after the recipient has opted-out, unless the recipient later gives affirmative consent to receive the e-mail (i.e., opts back in); and —the e-mail must be clearly and conspicuously identified as an advertisement or solicitation (although the legislation does not state how or where that identification must be made). Commercial e-mail is defined as e-mail, the primary purpose of which is the commercial advertisement or promotion of a commercial product or service (including content on an Internet website operated for a commercial purpose). It does not include transactional or relationship messages (see next bullet). The act directs the FTC to issue regulations within 12 months of enactment to define the criteria to facilitate determination of an e-mail's primary purpose. The FTC did so on December 16, 2004. Some requirements (including the prohibition on deceptive subject headings, and the opt-out requirement) do not apply if the message is a "transactional or relationship message," which include various types of notifications, such as periodic notifications of account balance or other information regarding a subscription, membership, account, loan or comparable ongoing commercial relationship involving the ongoing purchase or use by the recipient of products or services offered by the sender; providing information directly related to an employment relationship or related benefit plan in which the recipient is currently involved, participating, or enrolled; or delivering goods or services, including product updates or upgrades, that the recipient is entitled to receive under the terms of a transaction that the recipient has previously agreed to enter into with the sender. The act allows, but does not require, the FTC to modify that definition. Sexually-oriented commercial e-mail must include, in the subject heading, a "warning label" to be prescribed by the FTC (in consultation with the Attorney General), indicating its nature. The warning label does not have to be in the subject line, however, if the message that is initially viewable by the recipient does not contain the sexually oriented material, but only a link to it. In that case, the warning label, and the identifier, opt-out, and physical address required under section 5 (a)(5) of the act; must be contained in the initially viewable e-mail message as well. Sexually oriented material is defined as any material that depicts sexually explicit conduct, unless the depiction constitutes a small and insignificant part of the whole, the remainder of which is not primarily devoted to sexual matters. These provisions do not apply, however, if the recipient has given prior affirmative consent to receiving such e-mails. Businesses may not knowingly promote themselves with e-mail that has false or misleading transmission information. State laws specifically related to spam are preempted, but not other state laws that are not specific to electronic mail, such as trespass, contract, or tort law, or other state laws to the extent they relate to fraud or computer crime.