Common DIY Provisional Patent Application Mistakes: Not Describing the Invention in Enough Detail

This week I’m breaking down the 5 most common mistakes inventors make when filing a provisional patent application themselves, and how to avoid them.

Here’s Number One: Not Describing the invention in sufficient detail

Inventors often submit a few paragraphs, sketches, or even just an idea summary as a provisional patent application. But U.S. patent law requires the provisional application to fully enable someone skilled in the field to make and use the invention without undue experimentation.

Why Does This Matter?: If the description is too thin, it won’t support your later non-provisional patent application. If you leave out key technical details—like how a component functions, or what materials are used—you may not be entitled to claim those aspects later. You can’t add new content to a provisional application once it’s filed, and anything not disclosed in the provisional application can’t get the benefit of its priority date in a related non-provisional application.

Here’s how to avoid this mistake: Include a detailed write-up of how it works, what it’s made of, variations or alternatives, and any diagrams you have. Think like an engineer trying to build your invention from scratch—what would they need to know? Write all that down. Include materials, dimensions, wiring, workflows—whatever applies. Better yet, have a patent attorney help you so you are certain the description and drawings are sufficient.

I work with my clients to submit provisional patent applications that are nearly as detailed about the invention as a non-provisional application would be, while still allowing a some wiggle room for tweaking that often happens between the provisional filing date and when they’re ready to file the non-provisional application. That way I know the provisional application is going to support everything in the non-provisional application unless the client makes major changes. If anything, I will include more options and leeway in the provisional application, without being too broad, as it’s fine to narrow the scope of the non-provisional application and NOT fine to add anything that can’t be supported by the description and drawings in the provisional application.