United States copyright law recognizes that certain portions of software are protected by copyright law. Like other items protected by copyright law, copyright protection attaches to software as soon as it is "fixed in a tangible medium"--for instance, when written to a disk.
The Massachusetts Institute of Technology notes that, when computer software was first developed, U.S. courts did not recognize it as eligible for copyright protection. Copyright law requires a work to be presented in a "fixed, tangible medium." When computer software first appeared, courts saw it as intangible and labeled it a "utilitarian good" that arose from the running of source code on a machine.
In 1980, Congress added computer software to the list of works protected by copyright under the U.S. Copyright Act. Congress clarified the rules surrounding software copyright in the 1998 Digital Millennium Copyright Act, which prohibits disabling or scrambling a computer program's copyright management data.
Extent of Protection
The U.S. Copyright Office's Circular 61 explains that copyrights for computer software do not cover certain elements of software, including "ideas, program logic, algorithms, systems, methods, concepts, or layouts." These restrictions arise from U.S. Supreme Court cases in which the court separated the purely functional components of computer software from those that demonstrated "originality of design."
Software copyright law protects not only the literal software code from being copied, but also the program's design features and elements, as long as these show evidence of creativity or design.
End User Rights
Software copyright law also expressly permits software users to make copies in certain situations, no matter who owns or has registered the software copyright. Section 117 of the Copyright Act allows owners to make backup copies of their software "as an essential step in the utilization of the computer program," including computer maintenance. Similarly, someone who owns a copy of a computer program may sell that copy under Section 109 of the U.S. Copyright Act.
The Digital Millennium Copyright Act
The Digital Millennium Copyright Act (DMCA) was passed in 1998 to protect software copyright holders, as well as owners of other digital media, from illegal copying of their products. Among other things, the DMCA 1) prohibits circumventing commercial software's anti-copying or anti-piracy measures; 2) prohibits the "manufacture, sale, or distribution" of programs or devices used to circumvent software's anti-piracy measures, except when these items or programs are used to test anti-piracy measures or to conduct research on encryption; 3) allows nonprofit libraries, archives and educational institutions to make copies of software that is otherwise protected by anti-piracy measures; and 4) requires Internet service providers to remove software programs posted to users' websites, if the programs appear to be posted in violation of copyright. The fair use provisions of the Copyright Act are still available to individuals charged with copyright infringement under the DMCA.
According to its Circular 61, the U.S. Copyright Office will accept copyright registration applications that include a request for copyright protection of screen displays as well as computer software code. An application that seeks to register a screen display must list the display itself as a "visual arts work" and the code as a "literary work." For the screen displays, the application should list "computer program" as the author of the work.