
Apple's Collatz Hash Patent Application (2013) - deckar01
http://www.google.com/patents/US20130108038
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deckar01
I'm not sure this warrants a patent. Upon further inspection the only real
transformation they add to the Collatz function is returning the result modulo
some prime. This is a very generic operation that can turn any function into
hash-like mapping on a finite field.

They even had the nerve to include a generalization of the Collatz function in
the patent.

> The hash function can apply more complex variations, such as adding
> multiplication, addition, modulo or other operation(s) in the even and/or
> odd operations.

With this generalization one can accidentally construct a variation that
simplifies to an existing hash function (prior art?).

Should a patent really be allowed to control the use of an entire class of
functions?

How can a patent claim ownership of an infinite number of transformations on
an idea?

~~~
throwawaykf05
The only thing you should read when evaluating the scope of a patent or patent
application is the claims. In this case, the first claim is:

 _1\. A method comprising:

receiving an input value and an iteration value;

based on the iteration value, iteratively performing steps comprising:

if a least significant bit of the input value is 0,

(1) dividing the input value by a first value,

if a least significant bit of the input value is 1,

(1) multiplying the input value by a second value,

(2) adding one to the input value, and

(3) applying a modulo operation of a prime value to the input value, to yield
a first iteration value,

to yield an updated input value;

returning the updated input value as a hash value._

Note that the "first value" and "second value" can be numbers other than 2 or
3. Not even sure how that works.

Also, as the claim is currently written, it seems indefinite, or at least
incorrect, because it is unclear if the modulo In step (3) is applied to the
input value, or input value + 1, or the input value * second value, or (input
value * second value) + 1. An exact reading of the claim implies the former,
whereas what they probably want is the latter.

I'm not an expert in either of these areas - but how is cryptographic hashing
an obvious application of the Collatz function? Is there some well-known
property of Collatz sequences that make them suitable for crypto hashes?

~~~
deckar01
Cryptographic hashes have many different properties that make them useful and
distinct. The most fundamental properties the Collatz function shares with
hash functions include it being deterministic and non-invertable. Applying the
modulo operation to map the input/output to a finite field provides
uniformity. Change the function to b^k and you have the discrete logarithm
problem.

~~~
throwawaykf05
Thanks for the simple yet clear explanation.

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otterley
This is merely an application; the USPTO has not granted a patent based on it.

OP or mods, can you please update the title? It's currently factually
incorrect.

~~~
deckar01
Updated to reflect that the link refers to a patent application.

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vortico
How can someone even patent something I was able to come up with at age 14? As
a teenager I would have thought it was a stupid thing to patent, because it's
a straightforward reaction after learning of the Collatz conjecture. The US
patent office is beyond fucked.

And it's not even remotely cryptographically secure, or even fast.

~~~
deckar01
It's not that it is stupid, straight-forward, insecure, or slow.

The problem I see is that this patent claims ownership of an infinite number
of transformations that can be made to the Collatz function. There is nothing
novel about this. They state that it is used as a hashing function, yet
provide no property of the system that qualifies it to be a hashing function.

This belongs in a research paper, not in a patent.

~~~
throwawaykf05
Pretty much all patents are written in a way that can cover an infinite number
of variations of the core idea. The novelty here may actually be the use of
this as a cryptographic hash function. They give no supporting property, but
as my other comment asks, if such a property cannot be easily divined, it may
in fact be non-obvious.

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gojomo
Look, Apple's innovations and IP battles with other corporate behemoths
require a big patent attorney staff. But some weeks, there's more people than
genuine novelty to protect. Thus, a filler filing like this.

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bjblazkowicz
This is like metallica trying to patent a guitar riff.

~~~
deckar01
It is more like some person trying to assert copyright over all the ways you
can add, remove, or change the notes in one of Metallica's guitar riffs.

~~~
VeejayRampay
It is more like it's impossible to use a metaphor in the programming world
without someone correcting you with a different metaphor :)

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spacemanmatt
Fortunately, the SCOTUS clarified that abstract subject matter is still
ineligible. Even when you do it on a computer.

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monochromatic
> clarified

I don't think you and I read the same Alice v. CLS opinion.

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throwawaykf05
Unfortunately, most people just read the highly inaccurate 10-word summaries
that tech media outlets bandy about.

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monochromatic
As usual, somebody has found a patent _application_ , read the title and
nothing else, and decided it was alarming enough to post.

~~~
deckar01
Well, no. I read the patent application several days ago, in its entirety
(quite painful), because it relates to my current research. This patent
application could very well inhibit the application of my research and
discourage involvement by third parties.

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scottevi199
[http://www.uspto.gov/patent/initiatives/third-party-
preissua...](http://www.uspto.gov/patent/initiatives/third-party-preissuance-
submissions)

~~~
deckar01
The first step of the petition involved finding the "Confirmation Number" in
the USPTO's PAIR system. From here I was able to find out that the filing
status is "Abandoned -- Failure to Pay Issue Fee". Also of note is the fact
that the status was set to "Abandoned" only after the "Notice of Allowance and
Fees Due" was allowed to expire. The fact that the USPTO granted preliminary
approval to this patent application is troubling.

