To: Sergio Demian Lerner <sergio.d.lerner@gmail.com>,
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
References: <CAKzdR-pAxs_Gim-aFdjd4eQPY6vWsoEVafYwcjmBjit_dsH_wA@mail.gmail.com>
From: Matt Corallo <lf-lists@mattcorallo.com>
Message-ID: <57F18F5A.6010304@mattcorallo.com>
Date: Sun, 2 Oct 2016 22:51:06 +0000
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Subject: Re: [bitcoin-dev] About ASICBoost
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Replies to comments inline.

Matt

On 10/02/16 17:13, Sergio Demian Lerner via bitcoin-dev wrote:
> Please Peter Todd explain here all what you want to say about a patent
> of a hardware design for an ASIC.
> 
> Remember that ASICBoost is not the only patent out there, there are at
> least three similar patents, filed by major Bitcoin ASIC manufacturers
> in three different countries, on similar technologies.

This is a very misleading comparison. I am not aware of any other
patents on Bitcoin-specific ASIC technology which are practically
enforceable or which the owners have indicated they wish to enforce. Of
the two patents which you point out which were filed on essentially the
same optimization that ASICBoost covers, yours predates both of them,
invalidating both the Spondoolies one (which Guy had indicated he wished
to use only defensively) and the AntMiner one. Of course, as China is
notorious for ignoring international patent law, AntMiner's could
possibly still be enforced in China. Still, AntMiner has, like
Spondoolies did, indicated they have no intention of enforcing their
patent to limit competition, though without any legally-enforceable
commitment. This leaves only your patent as practical and likely to be
enforced in the vast majority of the world.

> That suggest that the problem is not ASICBoot's: you cannot blame any
> company from doing lawful commerce in a FREE MARKET.

If you had acted in a way which indicated even the slightest regard for
centralization pressure and the harm it can do to Bitcoin in the
long-term, then I dont think many would be blaming you. Instead of any
kind of open or transparent licensing policy, with price structures
designed to encourage competition, you chose to hide behind an opaque
website, asking people to simply email you and Timo to negotiate
individually.

> It is a flaw in Bitcoin design that could be corrected if the guidelines
> I posted in [1] had been followed.
> 
> [1]
> https://bitslog.wordpress.com/2014/03/18/the-re-design-of-the-bitcoin-block-header/

Optimizations to the hashing algorithm are not, themselves, "attacks" on
Bitcoin, as you claimed in your post at the time. Only when they are
used in a rent-seeking fashion to push for more centralization and lower
miner revenue do they become so. One of the biggest advantages of SHA256
in the context of mining is exactly that it is a relatively simple
algorithm, allowing for fewer large algorithmic optimizations (or, when
there are, more people are capable of finding them, as happened with
ASICBoost). This opens the doors to more competition in the ASIC market
than if only few people had the knowledge (or a patent) to build
efficient ASICs. While it is certainly true that the high-end
ASIC-manufacturing industry is highly-centralized, making it worse by
limiting those who can build Bitcoin ASICs from anyone with access to
such a fab to only those who can, additionally, negotiate for patent
rights and navigate the modern patent system, is far from ideal.

You claim that Bitcoin should have fixed the problem at the time, but
you posted a proposal for a hard fork, with the only argument given as
to why it should happen being that you thought you had an attack, but
cant yet "really tell if they could affect Bitcoin". Instead of
following up with more information, as you indicated you would, you went
and patented the optimizations and have gone on rent-seeking behavior since.