US Patent Search
Should You Do An Invention Patent Search?

US patent search - should you do your own ?

You may need to do an invention patent search, a patent number search, or even do an international patent search. All of these are doable with either money or a lot of your time.

You will find that there are contrary opinions on this subject. Particularly among small business people the additional cost of doing a good US patent search is a problem when they are just beginning the steps for getting a patent.

Let me be clear up front about my view on this subject - I think getting a US patent search done before pursuing a patent is crucial. But I also recognize the cost issue and I understand the rationale some use in recommending that you don't spend that money up front. I understand the rationale - I just don't completely agree with it.

So what I will try to do in my discussions here is talk a little about how you might consider dealing with patent searching if you are cash constrained in the beginning. So I am never going to tell you it is O.K. to skip the US patent search and go for the patent. But I will talk about how to keep the cost of searching down under different scenarios. First let me tell you simply why I think getting a patent search done is crucial.

I can think of at least three important reasons:

    1) The overall cost of getting a patent is expensive. Before you spend the big bucks you should get the best information you can as to the validity of your patent claim. It's like a poker game, you can ante a little up front to see another card, then only bet more if you get a positive result.

    2) Your patent practitioner (attorney or agent) should know the closest prior art before drafting claims. You cannot do that without a good US patent search.

    3) If you have never read competitive patents you will be very surprised how much you can learn - and how many good ideas you can come up with just from reading well written patents. Of course not all patents are well written - but that is another story.

O.K. - that's my story. And I want to be sure you understand that I am not saying that because I want you to hire me to do your US patent search. I really do think it is crucial.

Having said that we still need to explore cost effective ways to do a patent number search, an invention patent search, or even an international patent search. There are online patent search tools available that will enable you or your company to do their own search. And I will be telling you where they are and how to use them, or how to find a patent search service. Many of the online patent search services are free. And if I were you I would use only the free ones unless you search for a living.

There are also competent patent search firms available to do this for you. In my view there are compelling reasons to use a patent search firm,, preferably one skilled in reading the patent literature. But again, there can be equally compelling reasons to do it yourself.

Types of Searches

There are also different types of searches and they vary in cost. The simplest and most common patent search is what I call a patentability search. Here you are basically trying to determine if your inventive concept can be patented. The search is aimed primarily at novelty - meaning are there patents out there that anticipate your invention, making it very difficult for you to get a strong patent?

Sometimes people will ask instead for a freedom to operate search. They are not sure they want a patent but are concerned about whether they are free to operate. The basic question is - will my invention infringe any known patents? This involves a different skill set. In a patentability search your are examining the entire specification of the patent - in a freedom to operate search you are reading claim language. Because you can't infringe a patent - you can only infringe claims. And some folks are simply not skilled at interpreting claims - and don't clearly understand what constitutes infringement of a claim.

A much more serious and expensive search is done when you are in the middle of a patent infringement lawsuit. As you know an infringement lawsuit can be very expensive - especially if you are being sued for infringement and could lose. The first line of defense in this situation, before trying to prove you do not infringe, is to try to prove that your opponent's patent is invalid. So you spare no expense to search the entire planet to find some prior art that the patent office missed.

We are going to be talking primarily about cost effective patentability searches for now.

There is also the issue of geography. You can do just a US patent search, or expand that to a Canadian patent search, a European patent search, or a broader international patent search. Again, all are doable, it is only money and/or time.

A key first question - how can be sure you will find all the important prior art? The simple answer - you can't . The world of prior art is huge. Remember - it is practically everything ever published before your priority date. It is not just patents. But most patentability searches tend to focus on patents.

So in reality your goal is not to absolutely ensure you find all the prior art - you simply cannot do that without doing massive searches. Rather your goal is to significantly reduce the chances that you are trying to get a patent in the face of obvious killer prior art. And to do that with an affordable US patent search.

And I think that goal is achievable. In my years of doing this I feel pretty good that my searches have accomplished this. I have occasionally found prior art that convinced a client to stop the process and only rarely missed some really important art. But, as you can probably guess - I do not guarantee that we found everything.

In the articles under development below we will learn what search engines are available and we will discuss some good strategies for conducting a meaningful US patent search - or international patent search.

Again - if you need more information please ask.


Patent Search Engine
You may want to know where the good online search help is. Here is a short article listing many patent search engines.

Patent Search Strategy
Lets start with some basic thoughts on search strategy. Here is the basic approach I use to do a patent search. 

Patent Classification
Patent classification systems. Ask most professional patent searchers and they will probably tell you that any serious search will have include a through search of one or more of the classification systems.Here is how the US Patent Office classification system is organized.

Patent Search with Free Patents Online
Whether you do your own formal patent searches or farm them out - patent searching capability can be important. If you are looking for a really good and low cost (free) search engine you might want to consider this one.

A Freedom to Operate Primer
Sometimes you do a patent search as part of a freedom to operate study. Here is a short primer on how to do that.

Getting a Canadian Patent Search
What if you are primarily interested in a Canadian patent search? Here are some useful places to look.


US Patent Search
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Mike Ervin
Mike Ervin - Cost Effective Small Business Patent Protection.

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