Patents as a security mechanism

John S. Denker jsd at monmouth.com
Tue Jan 21 13:50:35 EST 2003


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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