Cite as: 542 U. S. 656 (2004) Opinion of the Court Since the passage of COPA, Congress has enacted additional laws regulating the Internet in an attempt to protect minors. For example, it has enacted a prohibition on misleading Internet domain names, 18 U. S. C. § 2252B (2000 ed., Supp. III), in order to prevent Web site owners from disguising pornographic Web sites in a way likely to cause uninterested persons to visit them. See Brief for Petitioner 7 (giving, as an example, the Web site "whitehouse.com"). It has also passed a statute creating a "Dot Kids" second-level Internet domain, the content of which is restricted to that which is fit for minors under the age of 13. 47 U. S. C. § 941 (2000 ed., Supp. II). B Respondents, Internet content providers and others concerned with protecting the freedom of speech, filed suit in the United States District Court for the Eastern District of Pennsylvania. They sought a preliminary injunction against enforcement of the statute. After considering testimony from witnesses presented by both respondents and the Government, the District Court issued an order granting the preliminary injunction. The court first noted that the statute would place a burden on some protected speech. American Civil Liberties Union v. Reno, 31 F. Supp. 2d 473, 495 (1999). The court then concluded that respondents were likely to prevail on their arigument that there were less restrictive alternatives to the statute: "On the record to date, it is not apparent.., that [petitioner] can meet its burden to prove that COPA is the least restrictive means available to achieve the goal of restricting the access of minors" to harmful material. Id., at 497. In particular, it noted that "[t]he record before the Court reveals that blocking or filtering technology may be at least as successful as COPA would be in restricting minors' access to harmful material online without imposing the burden on constitutionally protected speech that COPA imposes on adult users or Web site operators." Ibid.