> Are you aware of any precedent that "enabling" copyright infringement is tantamount to copyright infringement?

Short answer, I'm not aware of precedent prohibiting emulation on the grounds of "enabling" copyright infringement the way an emulator does. But even in the US with fair use, I don't think emulation is always legal, and regardless Nintendo doesn't really need to demonstrate copyright infringement because simply suing would be enough to burden emulator developers with legal fees. See the UltraHLE emulator situation [5]. (Tangent: In Japan, there is no fair use, so I think the harm of emulation to Nintendo's sales would be enough to violate some kind of copyright law in Japan.)

The rest of this comment (the long answer-but-not-really-an-answer) is mostly spitballing on my part.

> Copyright obviously protects against the retransmittal of the copyrighted work. If Yuzu hasn't done that, it isn't guilty of copyright infringement. Instead, Nintendo is arguing that if Yuzu didn't exist, fewer people would have committed copyright infringement. That in itself is not a copyright claim.

Here is the closest situation I'm aware of. In the US, there were criminal and civil cases against Team Xecutor, who made devices and software capable of circumventing the Nintendo Switch's measures against running unauthorized copies of games [1]:

> In September 2020, Canadian national Gary Bowser and French national Max "MAXiMiLiEN" Louarn were arrested for designing and selling "circumvention devices", specifically products to circumvent Nintendo Switch copy protection, and were named, along with Chinese citizen Yuanning Chen, in a federal indictment filed in U.S. District Court in Seattle, WA on August 20, 2020.[3] Each of the three men named in the indictment faced 11 felony counts, including conspiracy to commit wire fraud, conspiracy to circumvent technological measures and to traffic in circumvention devices, trafficking in circumvention devices, and conspiracy to commit money laundering.[4] Bowser handled public relations for the group, which has been in operation since "at least" 2013.[1][5]

The legal basis of the anti-circumvention criminal cases seemed to have been based on DMCA 1201 [2] (a statute prohibiting circumvention of technical protection measures [3] against access to copyrighted digital data/works/software), even if the purpose of the circumvention is not for actual copyright infringement), but the judge and the US Department of Justice took the estimated financial damages very seriously [4]:

> The public face of a notorious video game piracy group was sentenced today to 40 months in prison for two federal felonies, announced U.S. Attorney Nick Brown. Gary Bowser, 52, a Canadian national of Santo Domingo, Dominican Republic, pleaded guilty in October 2021 to Conspiracy to Circumvent Technological Measures and to Traffic in Circumvention Devices, and Trafficking in Circumvention Devices. At the sentencing hearing U.S. District Judge Robert S. Lasnik said, “These are serious criminal offenses with real victims and harm to the community.”

> “This piracy scheme is estimated to have caused more than $65 million in losses to video game companies,” said U.S. Attorney Nick Brown. “But the damage goes beyond these businesses, harming video game developers and the small, creative studios whose products and hard work is essentially stolen when games are pirated.”

What if there's no circumvention involved, like in the case of an emulator? Then DMCA 1201 doesn't apply. However, what about the effect of emulation on Nintendo's sales? If you can't mod a Nintendo Switch you bought to play unauthorized copies of Switch games regardless of whether you bought authorized copies, then why should you be able to use an emulator, which might as well be a modded Nintendo Switch in terms of harm to Nintendo's revenue? is something I think Nintendo could convince courts about.

Nintendo definitely believes that emulation which affects Nintendo's revenue should be treated as copyright infringement. Nintendo threatened a lawsuit against UltraHLE, a Nintendo 64 emulator [5]:

> Nintendo's response and UltraHLE's discontinuation

> Also notable for its time, UltraHLE was capable of playing commercial games while the console was still commercially viable, a feat which was ultimately noticed by Nintendo. In February 1999, Nintendo began the process of filing a lawsuit against the emulator's authors, along with the website hosting the emulator.[6] Speaking to PC Zone, Nintendo representative Beth Llewellwyn commented: "Nintendo is very disturbed that RealityMan and Epsilon have widely distributed a product designed solely to play infringing copies of copyrighted works developed by Nintendo and its third-party licensees. We are taking measures to further protect and enforce our intellectual property rights which, of course, includes the bringing of legal action."[7] Despite this, UltraHLE had grown beyond either its authors' or Nintendo's control. Subsequently, Epsilon and RealityMan abandoned their pseudonyms and went silent.[8]

I don't think copyright lawsuits in the US give a defendant an early dismissal opportunity for demonstrating that the defendant's emulator doesn't actually facilitate copying in anyway, so all Nintendo needs to do is sue to bankrupt the defendant with legal fees or to incentivize the defendant to agree to a settlement.

[1] https://en.wikipedia.org/wiki/Team_Xecuter

[2] https://www.law.cornell.edu/uscode/text/17/1201

[3] https://en.wikipedia.org/wiki/Copy_protection

[4] https://www.justice.gov/usao-wdwa/pr/public-voice-and-princi...

[5] https://en.wikipedia.org/wiki/UltraHLE#Nintendo's_response_a...