Ever wanted to revisit an old classic, play a game that was never brought to your country in your native language or test a “homebrew” game you made for a console but do not have the original console in question? With the magic of video game emulation, you can do it at the touch of a button.

Emulators are great tools, however they tend to be shaky in terms of being legal. Emulators can be both legal and illegal. Everything is dependant on the circumstances.

Emulators are defined as pieces of hardware or software that makes one computer system work like another. In the case of a video game emulator, the main/host system would be a computer or console and the other/guest system would be the video game console that it is trying to replicate.

The emulators work by loading files (known as ROMs for cartridge-based games and ISOs for disk-based) that contain whole video games inside the emulator to recreate that game on the host system as if it were playing on the original console.

There are several places where you can get the games for free, allowing you to revisit those classics without having to shell out hundreds of dollars in cash. Copyright laws have been brought up to attack the legality of this practice, however.

In 1998, the Interactive Digital Software Association, now known as the Entertainment Software Association, went on a “great sweep” shut down a large amount of the major game emulation sites on the internet within a six-month timeframe. In 1999, emulators rose back up into the mainstream and had two cases that determined the legal standing of such software.



Copyright was the basis of three major court cases that focused on quashing video game emulation: Sega Enterprises Ltd. v. Accolade, Inc. , Sony Computer Entertainment, Inc. v. Connectix Corporation and Sony Computer Entertainment America v. bleem.

Sega Enterprises Ltd. v. Accolade, Inc.

In 1988, the Sega Genesis was launched in Japan and would release in multiple other regions years after.

In order to combat piracy and unliscened games in areas that had loose copyright laws at the time (i.e. Taiwan), Sega took a hard stance on piracy and made foritified security for the Genesis.

This worked well for Sega, as it prevented unlicensed/pirated games for a time. It didn’t take too long for independent companies to find a way around the system.

Accolade, a company that created primarily PC games, wanted to port some of their games to the Genesis. The company was not able to get a liscencing deal with Sega due to the high cost of putting out games for the system.

“One pays them between $10 and $15 per cartridge on top of the real hardware manufacturing costs, so it about doubles the cost of goods to the independent publisher.” – Alan Miller, Co-Founder of Accolade, Ltd.

In addition, Sega required the games to be exclusive to their console, which would’ve compromised their already established PC presence.

Instead of paying for the liscence, Accolade bought a Genesis and used it to figure out the executable code of the security system from three Genesis games. They used the code to bypass the security system, effectively allowing them to play their games on the console without getting the liscening code from Sega.

Sega saw that Accolade, as well as many more companies, were able to get around the security system, so they built a more advanced system in order to make it harder for unliscenced cartridges to be played on the Genesis. With the release of the Genesis III came the “Trademark Security System” (TMSS).

The case brief describes the process of the system:

“When a game cartridge is inserted, the microprocessor contained in the Genesis III searches the game program for four bytes of data consisting of the letters ‘S-E-G-A’ (the ‘TMSS initialization code’). If the Genesis III finds the TMSS initialization code in the right location, the game is rendered compatible and will operate on the console.”

If the screen showed, but the game was unlicenced, this means that Sega would be able to sue for trademark infringement. This was the main tactic that Sega would employ if an unlicensed company would attempt to use the code to display the trademark.

At the Winter Consumer Electronics Show in 1991, Accolade wanted to show off their port of their puzzle game “Ishido: Way of the Stones” for the system. When they tried to use it on the Genesis III system, they saw that the game wouldn’t load because to cartridge was unliscenced. Their work-around no longer worked.

This led to them doing what they did previously: reverse-engineer the code from the Genesis III in order to keep their games on the console.

They did what Sega wanted them to do and promptly took them to court on Halloween of 1991 in the United States District Court for the Northern District of California, accusing them of trademark infringement and unfair competition in violation of the Lanham Act. Copyright infringement was added to the list later on in the case.

The Lanham (or Trademark) Act, passed in 1946, is a law that established federal rules regarding trademark infringement, trademark dilution, and false advertising.

Accolade filed a counterclaim, saying that Sega was lying about the source of their games by having the trademark screen appear before the game was loaded.

Sega claimed that Accolade infringed on their copyright by bypassing the security system, which Accolade agrued was fair use. Judge Barbara Caulfield did not accept the fair use claim, saying that Accolade was a game manufacturer and their works were for financial gain. This had her believe that their works competed directly with Sega’s licensed games, which resulted in a sales decrease for the licenced games.

Sega Engineer Takeshi Nagashim also showed two cartridges that ran on the Genesis III without the TMSS showing up, not showing how he was able to do it. This destroyed the counterclaim of Accolade.

The judge ruled in favor of Sega on April 3, 1992. She issued an injunction, or judical order, to stop Accolade from selling their Genesis games and to recall all of their games they released for the system.

On April 14, 1992, Accolade filed for a stay on the injunction that was pending appeal in the district court. Accolade appealed the verdict to the Ninth Circuit of the U.S. Court of Appeals, because the court did not rule on the injuction by April 21.

The stay was granted on the recall order of all of Accolade’s cartridges, but the injunction preventing their reverse engineering and development of Genesis software was maintained until August 28. The Ninth Circuit had it dissolved pending the appeal review.

In reviewing the case, the court considered many factors in its own analysis, examining trademark and copyright issues as separate entities.

The Ninth circuit wasn’t convinced by Nagashima showing the cartridge that did not display the trademark logo. They thought that Nagashima’s cartridges showed what one could do with knowledge of the TMSS.

They also thought that Accolade didn’t have the same amount of knowlege as Nagashima.

Having the technical knowldege needed to avoid displaying the trademark on the system was not considered public information to the market. This lead the Ninth Circuit to determine that Sega’s attempt to prove that the trademark display was not required for games to be played on the Genesis III was a faulty arguement.

“Sega knowingly risked two significant consequences: the false labeling of some competitors’ products and the discouraging of other competitors from manufacturing Genesis-compatible games. Under the Lanham Act, the former conduct, at least, is clearly unlawful.” – Stephen Reinhardt, Ninth Circuit Judge.

He also suggested that the TMSS violated the Lanham Act, since the system would possibly consistitute a monopoly, stifling competition.

The court decided that Sega had violated the anti-monopoly aspect of the act by utilizing its trademark to prevent software competition.

For the fair use claim, the court looked at the four aspects of fair use. Those aspects are:

The nature of the copyrighted work The amount of the copyrighted work used The purpose of use The effects of use on the market

Judge Reinhardt determined that the file carrying the TMSS data was only a small fraction of the work that was on the cartridge, meaning that the games qualify as fair use, since the data on the cartride was “overwhelmingly original” and would benefit the public because it would provide Sega’s liscenced games with healthy competition.

The Ninth Circuit also determined that Accolades games were not “direct competition” for Sega, as they were not found to affect Sega’s market in any significant way.

The district court’s verdict was overturned on August 28, 1992, saying that Accolade’s use of the code was fair use.

The case was settled on April 30, 1993 after many attempts to overturn the verdicts by Sega. This lead to Accolade becoming an offcial liscenced company under Sega. It was unknown if there were any discounts toward the cartridge production prices that Miller refered to. Both parties paid their own legal costs.

The verdict set a precedent for reverse engineering consoles, showing that if the material taken is only a small part of a much larger product, it is legal to use that material.

This opened the door for emulator creators to take the source code from a console, which would lead to the creation of such programs.

Sega v. Accolade also established that the functional principles of computer software isn’t protected by copyright law, but by a patent or trade secret. It also establised that reverse engineering copyrighted software to access information about the console’s functional principles is protected by the fair use doctrine if there is no other way to get that information.

This has garnered criticism from many saying that the verdict allowed the copying of legally protected programs for experiments of unprotected functions.

Sony Computer Entertainment, Inc. v. Connectix Corporation

This case from 2000 is the first legal case that revolves around an actual emulator. The final discision also took place in Ninth circuit Court of Appeals.

Connectix Corporation, a software company that mainly created programs for Mac computers, started to work on creating the Virtual Game Station (VGS) in July 1998. The VGS was designed to run Playstation games on Macintosh hardware, with plans to relase a Windows program.

They did this by reverse-engineering the firmware of the BIOS by using BIOS to develop emulation for the hardware. Connectix then created thier own BIOS using the original firmware to help take care of the bugs.

Connectix offered to have Sony give them support for the creation of the emulator, but Sony declined.

The VGS was finally completed in December and was released a month later.

Less than a month later, Sony filed a complaint accusing Connectix of copyright infringement and violations of intellectual property against Connectix. The move was seen favoribly by other game companies, such as Nintendo and Sega.

An injunction was placed on Connectix to stop using the Playstation BIOS and to stop them from selling the VGS. The court also moved to impound all of Connectix’s copies of the Sony BIOS and all copies of works using those BIOS (Thus, all of the data for the VGS).

Connectix appealed the ruling in the Courts of Appeals for the Ninth Circuit.

The Ninth Circuit based their discision on the Sega Enterprises Ltd. v. Accolade, Inc. case, since that was the only precedent that relates to using the code from a video game console. They looked at the four aspects of fair use like they did for the Sega/Accolade case.



For the nature of the content, the court did say that the BIOS deserved to be protected by copyright, but they also said that the firmware was determined to have a lessened copyright protection due to the fact it contained unprotected parts that could not be examined without recreating those same parts.

The court saw the aspect of “how much of the work was used” as unimportant to the case. Connectix did use the BIOS repeatedly, but the court said that the final product did not have infringing material.

The purpose of use, or the third aspect, was a hotly contended argument. Sony claimed that Connectix infringed copyright by making a large amount of firmware copies. The court denied the accusation, saying that the methods used were efficient and avoiding wasting their efforts by using lackluster methods (i.e. using only one copy of the firmware) was the basis of fair use.

The Ninth Circuit also ruled that Connectix’s use of the BIOS qualified as “modestly transformative” as it created a new way for people to play Playstation games.

Lastly, the effect on the gaming market was examined. The judges acknowgledged that the VGS could effect the market of the Playstation by saying that offering a platform would give Sony added competition.

“For this reason, some economic loss by Sony as a result of this competition does not compel a finding of no fair use. Sony understandably seeks control over the market for devices that play games Sony produces or licenses. The copyright law, however, does not confer such a monopoly.” – Court File, Sony Computer Entertainment, Inc. v. Connectix Corporation

The Ninth Circuit Court also reversed orginal court’s ruling determining that the VGS diminished Sony’s “PlayStation” trademark.

In order to win the debate in the Ninth Circuit, Sony had to show that the mark:

Was “famous” Was used commercially by Connectixs was used by Connectix after “the mark became famous” was hurt in quality after the use by Connectix, as it is used to distinguish Sony’s wares and service.

Connectix conceded that marks 1 and 3 were true, but the court argued the fourth point. The trademark diminshing was not found through Connectix’s use, as the court could not find substantial evidence of Sony’s reputation being hurt by its use on the VGS.

With all four of the points in Connectix’s favor, the Ninth Circuit overturned the orriginal disicion and lifted the injuctions placed on Connectix’s material.

Connectix tried to have Sony’s lawsuit dismissed and Sony tried to take the matter to the Supreme Court. After failures on both ends, they decided to settle the case. As a result, Sony bought the rights for the VGS a year later and discontinued the emulator on June 30, 2001. Connectix closed two years after.

This case established that the creation of another platform to play video games was considered legal in the United States. Not only would this help create more emulators, but it would also lead to companies creating those “5-in-1” consoles that could play several retro games.

Sony Computer Entertainment America v. Bleem

This last case is a little less lengthy and complicated than the previous two, but it involves the use of a Dreamcast and a PC to play Playstation games.

bleem! was a Playstation Emulator that was released in 1999, roughly the same time as the Connectix case. Rather than dealing with one lawsuit, Bleem Company president David Herpolsheimer and coder Randy Linden, the creators of the emulator, was subject to a lawsuit from Sony.

The project for the emulator started in 1998, with the goal of being the smoothest Playstation emulator around. Their methods were the same as the last two suits, they reverse engineered the console and worked out any bugs that came with it.

This still wasn’t enough to stop Sony from trying to take them down as a result of the 1998 takedown.

This is was in spite of the comany’s close attention to protecting the legality of their product.

“We don’t expect any problems from Sony. We’ve taken every possible step to ensure the security of not only our software, but have also worked to protect the rights of Sony and PlayStation developers in general. … So I don’t know how we can protect ourselves any more than we have,” said David Herpolsheimer, bleem! President and CEO



Sony filed the suit in March 1999, two days after bleem! started taking pre-orders for their emulator. The complaint issued by Sony claimed emulation software would increase the gaming “black market.”

Another issue was the value of Sony’s liscencing. They were worried that emulators would have developers and manufacturers and they would want to pay a lower fee to be liscenced under Sony.

“If Sony can’t retain a hold over the PlayStation, they’ll start to see us, the developers, balk at paying royalties,” said Spokesman Robert Stevens, Boss Game Studios.

In a suprisingly short set of suits, the courts ruled that bleem! wasn’t violating Sony’s rights or unfairly competing with the tech juggernaut. Sony lost on all counts, including bleem!’s use of in-game screenshots on its packaging. The court noted that bleem!’s screenshots was considered fair use and should be allowed to continue.



One court even went to far as to issue a protective order to “protect David from Goliath.”

Sony and bleem! shared a fair amount of animosity before, during, and after the suit. At a software expo in May 1999, members of Sony and bleem! staff caused an uproar because bleem! was using footage from the Sony-published Gran Turismo to show off its emulator prowess. Sony ended up having bleem! remove the monitors showing the emulator to avoid being kicked out.

The lawsuit ended up costing bleem! a good amount of money. According to a piece on bleem! from The Escapist, around one-fifth of the company’s income came went towards their legal battle.

That strain that came from the legal battle ended up being the death of bleem!, as they closed in November 2001, not long after they released the bleem!cast, which allowed Playstation games to be played on the Dreamcast.

While bleem! didn’t last long, the case did set precendent for smaller companies to be protected from larger companies and re-iterated that emulation is fair use.

Emulators are technically legal, but what about emulated copies of games?

Emulators have been tested in court, but computer copies of video game files, or ROMS, has not been tested in court.

Making back-up copies of video games are not legal, however. This was decided in the 1983 case Atari, Inc. v. JS&A Group, Inc., when Atari claimed that JS&A was infringing copyright and patents.

JS&A created a device called the Prom Blaster, used for the duplication of Atari 2600 cartridges. They marketed its use for creating back-ups of games owned by the customer.

This is becuase a rewritten portion of the Final Report of the National Commission on New Technological Uses of Copyrighted Works (CONTU) stated that archival copies of digital media should be only allowed “to guard against destruction or damage by mechanical or electrical failure,” and since game cartridges were not explicitly subject to mechanical or electrical failure, they were not protected under that classification.

The same could be said for disks in this day in age, as there have been very few (if any) cases that revisited creating back-up copies of media, either on a computer, a cartidge or a disk.

How to use Emulators legally

Given the information from these cases, here’s a step-by-step way on how to use them legally:

Get an emulator Use a legitimate copy of a video game (something that can run on the actual console you are trying to emulate) Insert the disk into the computer or use some sort of adaptor to insert the cartidge (I’m not sure of the legality of such adaptors). Use the emulator to run the files on the chosen form of media.

Downloading a file of a game you already own is a legally grey area. There were no cases that have determined a real legal ruling on such a case.

Emulation is legal, but it needs to be done in the right way in order to stay legal.