Patent Strategy: Advanced Patent Claim Drafting for Inventors

Blueprint for successIn an earlier article on patent claim drafting I discussed what you must do before you ever think about writing patent claims. See A prelude to patent claim drafting. Then in a follow-up article I discussed in a very basic way what must go into your patent claim. See The anatomy of a patent claim. Today we pick up our series with discussion of some advanced patent claim drafting strategies for inventors and others new to the art of claim drafting.*

Sometimes those who draft patent claims get a little too cute for their own good. What is it that you are trying to accomplish? Are you trying to get the broadest claim that you can possibly obtain? If that is your goal you will probably be rather disappointed with your efforts even if you are successful. Today it is very easy to challenge issued patent claims, indeed easier than ever before. That means your goal has to be to obtain the broadest valid claim possible, not just the broadest claim that you can sneak by a patent examiner.

Let’s use a specific patent as an example to illustrate the problem, which is one I see all too frequently when inventors represent themselves. US Patent No. 6,360,693 is simply titled Animal toy. If you look at the illustrations contained in the patent you realize this patent covers a great many things, including things that are obviously in the prior art. So, yes, on March 26, 2002, the United States Patent Office issued a patent on a what can be described as a stick.


Claim 1 of the ‘693 patent, which is the broadest claim in this patent, says that this “animal toy” has a solid main section, at least one protrusion and is adapted for floating in the water, which is extraordinarily broad. Claim 1 specifically reads:

1. An animal toy, comprising: (a) a solid main section having a diameter and a longitudinal length and extending a predetermined distance along said longitudinal length; and (b) at least one protrusion attached at one end thereof said main section and extending a predetermined distance therefrom and wherein said at least one protrusion includes a second longitudinal axis that is not in parallel alignment with a first longitudinal axis of said solid main section; and wherein said animal toy is adapted to float on the water.

While not every stick would infringe claim 1 of this patent, I would venture that there are many that would.  Ultimately, the claims to this patent were lost when the Director of the Patent Office ordered a reexamination. Still, some important lessons beg to be learned.

First, how is it possible that someone could have obtained such a ridiculously broad claim in the first place? Sometimes when you ask for a ridiculously broad claim on what a patent examiner considers a ridiculous invention they will give you what you seek. Perhaps it shouldn’t be this way, but you can understand the thought process. Patent examiners are given maybe 12-14 hours for an entire case of this complexity, which means in many instances patent examiners get to the end of their allotted time before they feel that they have done as exhaustive a review as necessary. So you ask them for claims that are just absurd and maybe they say FINE! Take them and I’ll move on to something more consequential, secure in the knowledge that you could never possibly enforce a claim on a stick against anyone.

Second, was there anything here that could have been patented? The answer is perhaps, but the drafting of the claims was so broad that nothing survived.

Let’s take a look at some of the dependent claims filed. Claims 2 through 15 read:

  1. The animal toy of claim 1 wherein said main section is formed of a rubber.
  2. The animal toy of claim 1 wherein said main section is formed of a plastic.
  3.  The animal toy of claim 1 wherein said main section includes a wood.
  4. The animal toy of claim 1 wherein said main section includes cellulose.
  5. The animal toy of claim 1 wherein said main section includes a flavoring.
  6. The animal toy of claim 1 wherein said main section includes a scent added thereto.
  7.  The animal toy of claim 1 wherein said main section is rigid.
  8. The animal toy of claim 1 wherein said main section is flexible.
  9. The animal toy of claim 1 wherein said main section is chewable.
  10. The animal toy of claim 1 wherein said main section includes a material that is lighter than water.
  11. The animal toy of claim 1 wherein said animal toy includes a fluorescent coating.
  12. The animal toy of claim 1 wherein said animal toy includes a camouflage coating.
  13. The animal toy of claim 1 wherein said animal toy is formed of wood particles.
  14. The animal toy of claim 1 wherein said animal toy is formed of wood chips.

A dependent claim incorporates by reference a previous claim and builds upon that previous claim to add additional specificity. Notice how each of these dependent claims refers back to and therefore depends on claim 1. Thus, claim 2 is to the stick covered in claim 1 where the main section is made of rubber. Claim 3 is to the stick covered in claim 1 where the main section is plastic. Claim 8 is to the stick covered in claim 1 where the main section is rigid. Claim 12 is to the stick covered in claim 1 where the main section has a fluorescent coating. You get the idea. Each claim builds on the stick and adds only a single characteristic.

If the broadest independent claim is not allowable what is the likelihood of that claim with 1 addition being allowable? When you do this and claim 1 is ridiculously broad there is very little reason to suspect any of your dependent claims will be anything other than ridiculously broad, and therefore unpatentable or ultimately invalid.

The other problem with this type of claim drafting, which is extremely common among inventors, is that you do not get any useful information from the patent examiner who is doing their job and will simply reject your claims. If you make it easy for the patent examiner to reject your claims after having done a quick or shallow search that is what will happen. Then if you amend your claims to overcome the prior art located by the examiner in that quick, shallow search they will do a more comprehensive search and almost certainly reject you again. The problem is the second rejection will be made final, which means you are going to need to file a continuation or a request for continued examination (RCE), both of which essentially cost you a new filing fee, to get further consideration.


Wait… how can an examiner finally reject me after I’ve addressed their rejections. Isn’t the second rejection by the examiner a new rejection? Almost certainly no, at least in this situation. If the examiner rejected you under 35 U.S.C. 102 for lack of novelty in the First Office Action on the Merits and then you amend your application and they still reject you under 102 for lack of novelty that is the same rejection for the second time even if the second time different prior art is used to reject your claim!

When you file a patent application you absolutely want to include claims that you believe at the time of filing could be allowed by the examiner. Indeed, file claims of varying scope, from broad to very narrow and everywhere in between. That will force a better search and more meaningful consideration by the patent examiner in the First Office Action on the Merits.

You want to draft every independent claim so that:

  • The most generic version of your invention is defined.
  • All of the pieces and parts are connected.
  • There is at least some difference when compared with the prior art.

You then sequentially add elements or characterizations (i.e., additional limitations) one by one in dependent claims. And you absolutely want to have at least one series of claims where you chain together dependent claims to dependent on the immediate previous claim creating ever more specific versions of your invention for the examiner to consider.

For example, consider this claim set:

  1. A widget comprising a piece and a part.
  2. The widget of claim 1 further comprising a thing.
  3. The widget of claim 2 further comprising a do-hickey.
  4. The widget of claim 3 wherein the thing is flat.
  5. The widget of claim 4 wherein the do-hickey spins.
  6. The widget of claim 5 further comprising a twist.
  7. The widget of claim 6 wherein the twist strobes.
  8. The widget of claim 7 wherein the piece tapers at the edge.
  9. The widget of claim 8 wherein the part curves.
  10. The widget of claim 9 wherein everything is made of transparent aluminum.

Claim 10 now covers a widget comprising a piece that tapers at the edge, a part that curves, a thing that is flat, a do-hickey that spins, a twist that strobes with all of the elements being made out of transparent aluminum.

By chaining together dependent claims you can find out what the examiner is willing to allow in terms of substance. You can almost always add enough elements and characterizations thereof to obtain a patentable claim. Every addition to a claim is a limitation, making it easier to get around your patent claims though, which is why you do not want to just have narrow claims and precisely why it is necessary to start as broad as you reasonably feel is possible and then step into more specifics little by little.

In truth, you may never do in 10 claims what the example above suggests, so don’t take it literally. One of my retired patent examiner friends refers to this strategy as a “fishing expedition,” where you basically are asking the patent examiner to figure out what is patentable. While there is technically nothing wrong with the strategy, having a working relationship with a patent examiner is an important matter. So you probably don’t need to chain every single dependent claim together like I showed here. I showed it here to illustrate a point, that by chaining claims together the last claim in the chain becomes quite specific, while previous claims are not quite as specific.

A strong patent will always have good, valid, broad claims, but will also have layers of claims with more specificity. This is true because while the narrower the claim the easier it is not to infringe, the narrower the claim the harder it is to be invalidated later. So a patent with only broad claims that are obviously invalid is completely worthless. A patent that has only very specific claims that are easy to get around is similarly not worth much. But a patent that has multiple claims at various levels of specificity can be quite strong.


Additional Information

For more tutorial information please see Invention to Patent 101: Everything You Need to Know. For more information specifically on patent application drafting please see:


* This and other articles on should not be viewed as encouragement for those who can afford professional assistance to cut corners and do things themselves. If you can afford to hire a patent practitioner you should. Of course, the more you read and understand the better prepared you will be to meaningfully assist your chosen patent attorney or agent. For many, however, the choice will be either to do it yourself or give up. The reality facing all entrepreneurs is that there is never enough time or money to do everything; that is the nature of being a start-up entrepreneur or serial inventor. This tutorial, and the many other articles on are required reading for those who have consciously decided to pursue a patent process on their own. Proceeding on your own comes with great risk. Read as much as you can, educate yourself to the greatest extent possible, and try and find professionals who will assist you piece by piece as necessary.


Warning & Disclaimer: The pages, articles and comments on do not constitute legal advice, nor do they create any attorney-client relationship. The articles published express the personal opinion and views of the author as of the time of publication and should not be attributed to the author’s employer, clients or the sponsors of

Join the Discussion

3 comments so far.

  • [Avatar for Srinivas Kathavate]
    Srinivas Kathavate
    February 14, 2017 03:44 am

    Srini @ Bangalore, India
    Hi Gene, Many of your articles pertaining to prior art and claims are of great help to me in deciding the format for my patent application. Thanks a lot for your tips and advise. As part of search in prior art have come across a patent #US 7980913 B1 that has 58 claims where in first 30 are unique while the remaining 28 claims are repetition of the first 30. Can you please clarify this anomaly, as I see. What is the max claim# an application can have? If claims exceed this threshold, what is the workaround?
    Sincere thanks and best regards.

  • [Avatar for Henry @ Morgan IAT]
    Henry @ Morgan IAT
    February 8, 2017 11:06 am

    The disclaimer at the end of your post really does a great job of summing up the best possible advice for anyone looking into patenting their idea.

    Apart from that a really excellent article that I’ll be pointing a few of our clients in the direction of. #Bookmarked 🙂

  • [Avatar for VinceS]
    February 1, 2017 06:20 pm

    Thank you very much for this additionally nuanced article Gene; it helps clarify my thinking of this meaty topic. As mentioned in my commentary on a claims article before, I am prototyping a thing where I have since realised (via the patent writing process and the excellent resources of the US patent office) that I have cracked the next level of development in a quite popular area for inventors. Finally I have managed to condense it down to the truly novel concept, somewhat akin to the concept of hover jets when only helicopters existed before – in that case it is separation of the lifting and thrusting job of the engine rather than changing the wing position (within obvious limitations!) to suit the need for lift and thrust. As you would appreciate, once you realise it is rotating the wing complete with the engine you invented, from that comes a whole lot of other stuff you do as well, which has been the essence of my confusion. I have described lots of the other stuff but detail varies as I am suspecting it is irrelevant; the problem then arises of not leaving a gap between what is taught and what is claimed.
    Because I need to go public I am very soon going to submit the provisional patent as drafted, complete with abstract, drgs, description and preliminary claims, just to lock it in. I don’t want any chance of later claimants saying I had not invented this stuff when they see the thing on the www and have their epiphanies, and start figuring out how to access the tech while they can’t see the text. I will have missed something, or got the wrong nuance, but a real patent lawyer can put in the full application, and handle the licence enquiries, and hopefully that will sort it!