One of the other protections available for software that is collateral to copyright is codified in the Digital Millennium Copyright Act (DMCA). The DCMA prohibits third parties from circumventing technological measures the owner uses to prevent unauthorized access to its copyrighted software. What is interesting is that in addition to civil remedies, there also may be criminal liability. Accordingly, the DMCA is one of the most controversial parts of the suite of IP tools available to software owners. Should a software owner wish to utilize this law or should a business believe that practice may contravene this law, it is highly advisable to seek competent counsel. 

That said, at a high level the law prohibits circumventing a technological measure used to protect against the unauthorized access to software or other copyrighted materials; tampering with software copyright notices and other copyright digital rights management information; and trafficking in any technology, product, or service that: (1) is primarily designed or produced for circumventing copy-control or other technological measures used to safeguard against the infringement of copyrights; (2) has only a limited commercially significant purpose or use other than to circumvent these copyright protections; or (3) is knowingly marketed for use in circumventing these copy controls or other technological copyright protection measures.

While the DMCA prohibits the circumvention of technological controls to gain unauthorized access to copyrighted materials, it does not prohibit the circumvention of technological controls that safeguard against the copying of these materials, other than by proscribing the trafficking in technologies and services designed primarily for this purpose. Additionally, there are a number of specific exceptions under the law that allow for reverse engineering to achieve interoperability, encryption research, and security testing.

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