Intro
A provisional patent application can include a written description of your invention, drawings that help explain it, and any supporting detail that shows how it works, how it’s made, and how it’s used. What it doesn’t need is formal patent claims, an inventor’s oath or declaration, or a list of prior art. That’s the whole point of a provisional filing, it strips out the formal requirements while still letting you describe the invention as thoroughly as you want.
The tricky part isn’t what you’re allowed to include. It’s making sure you actually include enough.
The Two Things Every Provisional Application Needs
Under 35 U.S.C. §111(b), a provisional application only has two hard requirements to get a filing date at all: a specification, and drawings if drawings are necessary to understand the invention. That’s a short list compared to what a nonprovisional application demands, and it’s exactly why provisionals are so popular as a first step.
A specification, in plain terms, is just a written explanation. There’s no required format or length. You could write two pages or twenty. What matters is whether the description actually enables someone else in your field to understand and recreate the invention without having to guess at the missing pieces.
What You Should Include, Even Though It’s Not Required
The USPTO doesn’t require formal claims in a provisional, but that doesn’t mean you should leave out detail. Here’s what a strong provisional application typically covers:
- A clear explanation of the problem the invention solves
- How the invention is built, assembled, or structured
- The materials, components, or software elements involved
- How someone would actually use it, step by step if that’s relevant
- Any variations, alternate designs, or different ways the invention could be built
- Drawings, sketches, or diagrams if a visual would help explain any of the above
That last bullet about variations matters more than people expect. If your nonprovisional application later tries to claim a version of the invention that your provisional never actually described, that part of your claim won’t get the benefit of the earlier filing date. The provisional only protects what it discloses, not what you meant to disclose.
What You Cannot Include or Do After Filing
A few things are off-limits once you’ve submitted a provisional application.
No Information Disclosure Statement
Provisional applications aren’t examined, so there’s no reason to submit a list of prior art references the way you would with a nonprovisional filing. Including one won’t help you and isn’t part of what the USPTO expects here.
No Amendments After Filing
Once your provisional is filed, you generally can’t go back and add new material to it. Small corrections to comply with formatting rules are allowed, but you can’t substantively expand the description after the fact. If you come up with an improvement a few weeks later, the standard approach is filing a separate provisional application to cover it, rather than trying to tack it onto the original.
No Formal Claims Required
You’re allowed to include claims if you want to, some inventors do as a way of organizing their thinking, but the USPTO doesn’t require them and won’t examine them even if you include them. What they will look at, eventually, is whether your specification supports the claims you write into your later nonprovisional application.
Provisional vs Nonprovisional Content Requirements
| Content Element | Provisional Application | Nonprovisional Application |
|---|---|---|
| Written specification | Required | Required |
| Drawings | Required if needed to understand the invention | Required if needed, and must follow formal drawing standards |
| Formal patent claims | Not required | Required |
| Inventor’s oath or declaration | Not required | Required |
| Information disclosure statement | Not accepted or expected | Allowed and often filed |
| Can be amended after filing | Only for formatting compliance | Yes, through the examination process |
This article gives general information about USPTO filing requirements and isn’t legal advice. What belongs in your specific provisional application depends on your invention, so it’s worth having a registered patent attorney or agent review your description before you file, particularly if the invention is complex or you plan to raise funding based on the filing.
Frequently Asked Questions
Do I need to include patent claims in a provisional application?
No. The USPTO doesn’t require formal claims in a provisional filing. Some inventors include a rough claim or two anyway just to organize their thinking, but it isn’t necessary and won’t be examined.
Can I include multiple inventions in one provisional application?
Yes, a provisional application can cover more than one invention or variation, since there’s no restriction requirement the way there is with a nonprovisional application. Just make sure each one is described in enough detail to stand on its own later.
Is there a page limit for what I can include?
Not exactly a hard limit, but the USPTO charges an additional application size fee once your specification and drawings together exceed 100 sheets, so unusually long filings can cost more than the base fee.
Can I add new information to my provisional application after I’ve already filed it?
No, not substantively. You can only make corrections needed to bring the application into compliance with formatting rules. If you develop something new, file a separate provisional application to cover it.
Do drawings need to meet formal USPTO drawing standards in a provisional application?
No. Formal drawing requirements apply to nonprovisional applications, not provisional ones. Clear sketches or diagrams are fine at the provisional stage as long as they help explain the invention.
What you can include in a provisional application is broad, but what you should include is the real question worth spending time on. Write the description like it’s the only chance you’ll get to explain the invention, because in a legal sense, for anything you leave out, it actually is.