Online copyright laws exist to protect creators of copyrighted content from having their works stolen or misused on the Internet. One of the largest and most controversial online copyright laws is the Digital Millennium Copyright Act, also known as the DMCA. Signed into law in the United States in 1998, the Digital Millennium Copyright Act implemented in America two treaties of the World Intellectual Property Organization relating to online copyright laws. The Digital Millennium Copyright Act strengthened the penalties for Internet copyright infringement. The Act also criminalized the creation and dissemination of technology designed to circumvent copy prevention programs with regard to copyrighted works. The DCMA also gave protection from copyright liability to Internet service providers. The law states certain safe harbor guidelines, allowing ISPs the opportunity to block access to copyright infringing material when notified by the copyright holder. The DCMA does not have clear rules regarding websites that simply link to infringing content, leaving many gray areas with regard to online copyright laws.