copying it.78 Sometimes in the process of reverse engineering, code on the original platform is decompiled or disassembled into an intermediate form so its behavior can be determined.79 The disassembly or decompilation of code for such study could be interpreted as creating a derivative work, which is illegal activity under copyright law. To prevent legal challenges to reverse engineering, it is generally carried out by two different people under a “clean room” technique: one person writes the specification and the other later codes the result, so that the coder has not seen the original code.80 In
, the Ninth Circuit Court of Appeals decided that disassembly falls under the fair use provision, stating:
We conclude that where disassembly is the only way to gain access to the ideas and functional elements embodied in a copyrighted computer program and where there is a legitimate reason for seeking such access, disassembly is a fair use of the copyrighted work, as a matter of law. 81
The Digital Millennium Copyright Act (“DMCA” of 199882
codified the Ninth
ruling by granting reverse engineered products an exemption from copyright
infringement claims as long as firms met the following conditions:
§ 1201(f). Reverse engineering. This exception permits circumvention, and the development of technological means for such circumvention, by a person who has lawfully obtained a right to use a copy of a computer program for the sole purpose of identifying and analyzing elements of the
78 79 80 81 . . . Sega Enters. v. Accolade, Inc., 977 F.2d 1510 (9th Cir. 1992) (holding that the reverse engineering of a p r o d u c t , i n c l u d i n g t h e d i s a s s e m b l y o f t h e o r i g i n a l c o d e t o u n d e r s t a n d f u n c t i o n a l i t y , w a s p e r m i s s i b l e , e v e n done for eventual third-party commercial use). engineering. i f is commonly cited as upholding the legality of reverse
Accolade, a noted developer of videogame software, had produced six unlicensed games for the Sega Genesis home videogame console. Sega promptly sued Accolade, claiming copyright and trademark violation. The courts upheld Sega's contentions, but the decision was later partially reversed upon appeal. The Ninth Circuit Federal Court found that it was “fair use” for Accolade to dump and decompile the internal codes of the Sega Genesis and its games for developmental purposes, provided there was no other way to gain access to the concepts involved in their operation. This would have permitted Sega to establish a de facto monopoly over games for the console, which would have been unfair to Accolade. However, it was also ruled illegal for Accolade to activate the Sega Trademark Security System (TMSS) within these unlicensed games, however unintentional that may have been, since this gave the wrong impression that Sega had authorized Accolade's unlicensed titles when in fact they had not. Sega and Accolade eventually settled their differences out of court.
is the case most frequently cited regarding the legality of reverse engineering. This is the case upon which the reverse engineering clause of U.S. copyright law is based (US 17 CR 1201(f)). It introduced the legal concept of the “intermediate copy”—a copy of copyrighted computer code generated from an original vendor product in order to develop a non-infringing product. It does not matter how the intermediate copy is produced so long as it is made, but it is significant to note that this dispute involved the dumping and disassembly of object code originally stored in ROM.
82 See U.S. Copyright Office § 107 (1-4) (2004), http://www.copyright.gov/title17/92chap1.html#107 (last visited July 4, 2004).