
How to Read a Patent - teachingaway
http://adlervermillion.com/how-to-read-a-patent/
======
throwawaykf05
A slightly more humorous take on the same thing:

[http://www.danshapiro.com/blog/2010/09/how-to-read-a-
patent-...](http://www.danshapiro.com/blog/2010/09/how-to-read-a-patent-
in-60-second/)

~~~
jballer
Former patent examiner here. This is the truth. Only thing I'd add is, read
the claims _broadly_. Anything that could possibly be meant by the words in
the claim.

If it's broad enough to contemplate what you're doing, look through the spec,
correspondence (the "file wrapper"), and general knowledge at the time for
arguments to restrict interpretation of scope. Also, talk to a lawyer :(

edit: linked to this in another comment, and it also belongs here: "Broadest
Reasonable Interpretation"
[http://www.uspto.gov/web/offices/pac/mpep/s2111.html](http://www.uspto.gov/web/offices/pac/mpep/s2111.html)

~~~
ThomPete
Would you say it's more or less impossible to write your own patent claim?
I.e. is there some book or some resources that could teach you to do it or is
the knowledge required too big?

~~~
teachingaway
Mostly impossible. There is a fairly useful book - the USPTO's "Manual of
Patent Examining Procedure" (or MPEP). Official -
[http://www.uspto.gov/web/offices/pac/mpep/](http://www.uspto.gov/web/offices/pac/mpep/)
My copy - [http://adlervermillion.com/MPEP/](http://adlervermillion.com/MPEP/)

Its a huge book though, and not worth reading it unless you want to work with
patents every day (as a patent agent, patent examiner, patent lawyer).

Also, its a reference book, not really something you can read start-to-finish.

------
WildUtah
Only the claims define the power to block others from using the ideas in the
patent.

In theory.

But remember that the patentee (that's the one with the patent) can always
keep a "continuation" pending. With a continuation, the patentee can rewrite
the claims however he wants. He can wait until your product is on the market
and rewrite his claims to follow your product exactly. He could even sue you,
lose for invalidity or noninfringement, and then rewrite his claims to more
closely match your product and sue you again.

The only limit on claim rewriting is that the new claims have to somewhat
reflect what's in the specification and have to be reexamined. Reexamination,
like examination, is more a coin flip than an engineering evaluation of the
patent claims. Reflecting the specification doesn't have to follow too closely
what was in there originally but it does place some limit on the breadth of
claim rewriting.

And rewritten claims have the same long ago priority date against prior art as
the original claims. Your product does not count as prior art just because it
was widely known when the new claims are written.

------
ww520
One common confusion people have when reading patent is the word "comprise,"
which appears a lot in the claim language. This probably comes from the
confusing definition of the word in the legal dictionary, [http://legal-
dictionary.thefreedictionary.com/comprise](http://legal-
dictionary.thefreedictionary.com/comprise), which implies there are more
elements than the ones specified.

Comprise always means all or nothing in the claim conditions. All conditions
have to be satisfied for the claim to be valid against a product.

~~~
jballer
"Comprising" means having at least all of the listed elements.

"Consisting of" means having all of the listed elements and nothing more.

"Consisting essentially of" means having all of the listed elements, with more
stuff that doesn't _materially change_ the character of the invention (that's
where the lawyers come in).

[http://www.uspto.gov/web/offices/pac/mpep/s2111.html](http://www.uspto.gov/web/offices/pac/mpep/s2111.html)

------
javajosh
Having read this article, I begin to suspect that _only the claims define
patent rights_ , and not any other section of the patent.

~~~
teachingaway
Its the number one mistake people make... but maybe I should tone down the
repetition a little?

~~~
icegreentea
No. Keep it the way it is. The number of times patent stuff shows up on HN and
people go read the abstract or description, or just the title, and then go get
outraged is (hehe) outrageous. This needs to get hammered into people's heads.

~~~
gfodor
sadly, this won't stop them, as I'd wager more than a few of them know that
the abstract has no legal weight, but are always up for an excuse to bash
their particular company/individual of choice who files software patents.

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leoc
Assuming of course that it's a smart idea to be reading that patent at all...

------
analog31
>>> Check to see whether the prior art reference explains every element of a
claim in the patent. If so, the reference “anticipates” the claim, and the
claim is invalid.

I'm not a lawyer, but I have over a dozen patents, and have participated in
other IP related activities such as invalidation. Here is how I understand it,
as explained to me:

It's assumed by default that the patent is granted in light of the information
referred to by cited works. In other words, the examiner has declared that
nothing in the references anticipates the claims. If you're looking for new
prior art, it has to be outside of those references.

Of course anything can be challenged, but instead of "look, we found some
prior art," you have to argue, "look, the examiner missed something."

OP, does that make sense?

A couple other thoughts: First, the body text may be gibberish, but the body
of patent A can be used against the claims of patent B, if A is not cited by
B. I've used this successfully, thanks to a few solid days of Google
searching. Or, A and C can be combined to show obviousness.

Second, body text can contain useful information in its own right. I have a
product under development right now for my side business, using an electronic
circuit described in an expired patent.

------
habith
Interesting read, thank you for posting it.

One suggestion is to copy/move the warning "If you have an important patent
question, hire a patent lawyer" to the intro.

A lot of people skim through the conclusion section and may just know enough
now to be dangerous, like you said :)

------
malkia
Q: How To Read a Patent A: If you work in a company, then the answer is very
simple: "Don't!" \- Don't even try to pretend that you've heard it, or that it
exist.

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rjdagost
Only claims define the intellectual property rights, I get that. But patent
jargon is often so abstruse and vague that you need to read much of the
supporting text to even understand the claims. Sometimes when I look at claims
for patents that I'm an inventor on even I don't know what IP is being staked
out based on the claims section alone.

~~~
tjradcliffe
One trick I find very useful is to read the claims out loud. It forces me to
slow down and concentrate on the words.

Also, some patent lawyers have a "said fetish": every component is referred to
as "said component" so you get sentences like "A widget consisting of a foo, a
bar and a finangle, with said foo afixed atop said bar and said finangle to
make an assembly where said assembly has said foo..." etc. The presence of the
"said"s makes the claims weirdly unreadable, as they grab scarce attention
from the lay reader, so just blip over them when reading.

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Xdes
I wish someone would write "how to read an IETF specification" or "how to read
an ECMA standard."

------
skeoh
Here's a link to a patent on Google Patents for example:
[https://www.google.com/patents/US5255452](https://www.google.com/patents/US5255452)

You can see how Google emphasizes the independent claims on the right.

------
fastball
I think we killed it :(

Here is a cache of the homepage though...

[http://www.salar.ly.nyud.net:8080/](http://www.salar.ly.nyud.net:8080/)

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thomasfoster96
I've needed this for a while.

