Patents as a security mechanism

2003-01-21 Thread Matt Blaze
Patents were originally intended, and are usually used (for better
or for worse), as a mechanism for protecting inventors and their
licensees from competition.  But I've noticed a couple of areas where
patents are also used as a security mechanism, aiming to prevent the
unauthorized production of products that might threaten some aspect of a
system's security.

One example close to home is the DVD patents, which, in addition to
providing income for the DVD patent holders, also allows them to prevent
the production of players that don't meet certain requirements.  This
effectively reduces the availability of multi-region players; the patents
protect the security of the region coding system.

Another example I've found is in the world of mechanical locks, where
one of the biggest security threats to users comes from the unauthorized
duplication of keys.  High-security lock manufacturers try to create
key designs that are novel enough to be patented, and advertise the
patents (and the fact that keys have tightly controlled distribution)
as a selling point.  Many users actually prefer these patented products
because even though it means they might have to pay monopoly prices for their
keys, it makes it less likely that a thief will be able to get a duplicate
at the corner hardware store.  I'm a bit skeptical about whether this
really is effective (and at least one legal case, Best v. Ilco, casts some
doubt on the validity of many of the key blank patents) but it's standard
practice in the lock industry.

Are there other examples where patents are used as a security mechanism?

-matt



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Re: Patents as a security mechanism

2003-01-21 Thread Ben Laurie
Matt Blaze wrote:

Patents were originally intended, and are usually used (for better
or for worse), as a mechanism for protecting inventors and their
licensees from competition.  But I've noticed a couple of areas where
patents are also used as a security mechanism, aiming to prevent the
unauthorized production of products that might threaten some aspect of a
system's security.

One example close to home is the DVD patents, which, in addition to
providing income for the DVD patent holders, also allows them to prevent
the production of players that don't meet certain requirements.  This
effectively reduces the availability of multi-region players; the patents
protect the security of the region coding system.


FWIW, the precedent was set in a lesser way with CDs - there is an area 
that isn't writable on CD-Rs, which can be prefilled at manufacture 
time. AFAIK, no-one ever actually used it as a security mechanism, but 
it was there.

On a related note, you could licence either data-only or data and music 
from Phillips (or is it Philips?), and they were pretty aggressive about 
protecting it (I know because I wrote one of the first rippers [CD-Grab] 
and they used to get excited about it periodically, since it worked on 
data-only drives).

Cheers,

Ben.

--
http://www.apache-ssl.org/ben.html   http://www.thebunker.net/

There is no limit to what a man can do or how far he can go if he
doesn't mind who gets the credit. - Robert Woodruff


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Re: Patents as a security mechanism

2003-01-21 Thread John S. Denker
Matt Blaze wrote:


Patents were originally intended, and are usually used (for better
or for worse), as a mechanism for protecting inventors and their
licensees from competition.  

That's an oversimplification.  Patents were originally
intended as a bargain between the inventors and the
society at large.  Under the terms of this bargain, the
inventors make public (which is the root meaning of
patent) the details of the invention, rather than
thereby advancing general knowledge and permitting
follow-on inventions.  In exchange the inventor was
granted limited protection from competition.  In the
absence of a patent system, inventors will try to
keep everything a trade secret, which is another way of
fending off competition for a while.  From society's
point of view, patents are generally better than trade
secrets.  From the inventors' point of view, patents
are generally better than trade secrets.  So we have a 
mutually-beneficial bargain.  Patents were originally
intended to be a win/win proposition.

Of course it is axiomatic that whatever you're doing,
you can always do it wrong.  We can debate whether the
current system fulfills the original intention, but
let's not go there right now.

But I've noticed a couple of areas where
patents are also used as a security mechanism, aiming to prevent the
unauthorized production of products that might threaten some aspect of a
system's security.


OK.


... mechanical locks ...  Many users actually prefer these patented products
because even though it means they might have to pay monopoly prices for their
keys, it makes it less likely that a thief will be able to get a duplicate
at the corner hardware store.


An interesting observation.

 I'm a bit skeptical about whether this really is effective

So am I.

 (and at least one legal case, Best v. Ilco, casts some

doubt on the validity of many of the key blank patents)


It's amusing that Best had a utility patent and a
design patent, both of which were held invalid (on
different grounds).  It is the design patent which
I think speaks most clearly to the point Matt is
making.
  http://www.law.emory.edu/fedcircuit/aug96/95-1528.html

==


One example close to home is the DVD patents, which, in addition to
providing income for the DVD patent holders, also allows them to prevent
the production of players that don't meet certain requirements.  This
effectively reduces the availability of multi-region players; the patents
protect the security of the region coding system.


The following sounds like a nit, but I think it is
more than that:  I think it is the _CSS licenses_
rather than the DVD patents that play the role
of protecting the region coding system and reducing
the availability of multi-region players.

This gets back to the bargain discussed above,
because the CSS license is based, as far as I can
tell, on trade secrets.  No particular patents are
mentioned in the CSS license forms I've seen;
instead there is much mention of Highly Confidential
Information.

Perhaps a more important point is the economic angle.
Let's re-examing the statement:
 Many users actually prefer these patented products

We need sharper terminology.  We need to unbundle
the products;  that is, we have a _lock_ product
and a _key_ product.  It is unsafe to assume that
whoever buys the lock product is the same person
who buys the key product.

Whoever pays for the locks has a vested interest
in high-security locks that open to as few keys
as possible.  Whoever pays for the keys, on the
contrary, has a vested interest in keys that are
extra-powerful and/or cheap and extra-widely
available.

Suppose some party Alice controls a restriction,
such as a patent or trade secret.  Alice will try
to sell the restriction to the lock-buyer, Larry,
who benefits directly from the security.  Larry
won't buy it unless he is convinced that Alice is
willing and able enforce the restriction against
key-makers and key-buyers such as Kathy.


Are there other examples where patents are used as 
 a security mechanism?

Not that I know of.

So we have a grand total of less than one valid
examples.
 -- CSS depends on secrecy, which is by definition
the opposite of patentcy.
 -- Best v. ILCO held that patenting key-blanks is
an abuse of the design-patent law.

I think this is as it should be.  That's not the
proper purpose of patent law.

Of course if you ask about non-patent laws, there
are many examples:
 -- in some jurisdictions it is illegal in general
to carry lock picks.
 -- in some jurisdictions it is illegal in general
to copy a key marked do not duplicate.
 -- copyright law is sort of a do not duplicate
stamp protecting original creative works against
certain types of duplication.
 -- DMCA makes it a federal criminal offence to
circumvent triple-rot-13.


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Re: Patents as a security mechanism

2003-01-21 Thread Matthew Byng-Maddick
On Tue, Jan 21, 2003 at 11:02:25AM -0500, Matt Blaze wrote:
 One example close to home is the DVD patents, which, in addition to
 providing income for the DVD patent holders, also allows them to prevent
 the production of players that don't meet certain requirements.  This
 effectively reduces the availability of multi-region players; the patents
 protect the security of the region coding system.

Related to this, some years ago is the games console industry. The DVD
CCA is by no means the first to do such a thing.

MBM

-- 
Matthew Byng-Maddick [EMAIL PROTECTED]   http://colondot.net/

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