How important are claims in provisional patents

Question

Is it important to mention the claims in a provisional patent and how will the claims affect the non-provisional patent if I decided to convert it within a year? I have read that you cannot mention the claims in the non-prov patent if you did not write them in the provisional patent. Is that true? I want to write them but they are not easy to write and I am afraid that writing them wrong would hurt my chances on the invention.

Answer 1

There is no requirement for claims

Provisional applications are not examined, and therefore have no formality requirements. As long as they are validly filed, it doesn't matter precisely what format they are in.

But including claims in a provisional is good

One key purpose of a provisional is to for a later non-provisional or Convention application to be entitled to an earlier date. This only occurs if the invention claimed in each claim of the non-provisional was present in the provisional.

If the claims of the non-provisional match the claims of the provisional, then this is very clear. And this is where the key benefit lies. By having claims in your provisional, you are making abundantly clear that you are entitled to an earlier date.

Conversely, if there are no claims (or claim-like language) in the provisional, there is an increased risk that the claims of the non-provisional will not be entitled to the earlier date. But it all comes down to risk, and if you are careful with your drafting, you can minimise this risk. But why take the risk if you can avoid it simply with claims?

Is it true that you cannot mention the claims in the non-provisional if you did not write them in the provisional?

No. While it may be good practice to match them up, there is no obligation to have claims in the provisional.

In fact, it is not uncommon for you to need to completely redraft the claims for the non-provisional (perhaps due to further development). This is fine. However, having some kind of claims in the provisional may still be beneficial: you're not obligated to use them in your non-provisional, but you can if they are helpful.

Claims are not easy to write

That's true: they are certainly the hardest part of any patent application. But there is a strong argument for starting with the claims before the description. The purpose of the description is to support your claims: it has no real value on its own. So by starting with the claims, you can ensure that the language in the claims is reflected in the language of the description.

If you start with the description (where you have much more literary freedom), you may end up with language which reads well but doesn't quite suit a good claim. It's not impossible to draft claims last, it's just more difficult.

Answer 2

I think, very. As noted in the other answer, there is (probably) no legal requirement for claims. However, the whole purpose of the provisional filing is to give you a date for the invention. If you do not write the claims, chances are you will not actually set out the invention, but only one or a few specific implementations. This can get tricky. A particular issue being that what you consider to be non-essential limitations will be considered to be part of the invention as set out. This is especially a problem in the EPO (and probably more-so in China, which is very literal-minded about support for language in the claims being found in the application as filed), but can also happen in the USA, where they are generally more flexible. The problem is directly caused by the application not clearly setting out what is non-essential.

Example

You invented the 1-2-3-4 cake. you write a disclosure stating:

• 1 cup (240 mL) butter
• 1 cup milk
• 1 teaspoon vanilla extract
• 2 cups sugar
• 3 cups flour
• 3 teaspoons baking powder
• 3 pinches salt
• 4 eggs

When you file non-provisional, you realize that milk could be replaced by orange juice. That was not described, so you figure you can get away with a claim that says:

• 1 cup (240 mL) butter
• 1 cup liquid
• 1 teaspoon vanilla extract
• 2 cups sugar
• 3 cups flour
• 3 teaspoons baking powder
• 3 pinches salt
• 4 eggs

Sorry, no support. So you say, lets try leaving out the milk altogether. No can do - a cake cannot be made without liquid. Some type of liquid really is an essential element and many patent offices will insist on finding it in the claim. Now you wish the disclosure had said "a liquid such as milk".

Or, you decide that vanilla is really optional, so you write a claim leaving it out. Again, if the disclosure did not say vanilla is optional, leaving vanilla out is not supported by the priority application. You will need to (and probably fail) to prove that somebody reading your disclosure would understand that vanilla is not part of the invention as conceived and described in the provisional application. Now you wish the disclosure had said "an optional flavoring such as vanilla".

And forget about changing the ratios between the ingredients (like cutting away some fat). Again, there is no support for that.

All this could be avoided had you tried to figure out the metes and bounds of the invention you want to protect. Once you do that, drafting reasonable claims (even if formally improper) is a piece of cake. Of course, you would also want to update your disclosure to support your new understanding of what you invented (as opposed to what you implemented).

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clarification: I do not mean to suggest that you start by drafting claims. That is very difficult. Instead, after you draft what you think is your disclosure, put in the hard work of figuring out your invention. Then you can draft some claims, and then you need to fix your disclosure so it reflects your understanding of the invention.

A useful tip: Once you have the disclosure written and try to figure out a claim/inventive concept, you can now compare the "claim" to the written disclosure and consider if perhaps your disclosure is too narrow or if your claim is too narrow. I find it much easier to consider the breadth of a claim when both the claim and the disclosure are in writing and can be compared.

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Often, the above issues with the provisional filing cannot be cured, due to publication before the non-provisional filing.

The rule to remember is "a disclosure sufficient to invalidate is not always sufficient to (usefully) patent". In this case, if you published your recipe, replacing the milk or leaving out the vanilla is probably an obvious variant. But they are not described, not is the invention set out as not including them. So the same disclosure which is not sufficient to obtain a patent on OJ-based cake, is sufficient to prevent you (or anybody else) from getting one.

This usually manifests as a one-two combination of writing an article, filing it as-is as a provisional application and then publishing.

see also patently-o.