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Top Mistakes Inventors Make With Provisionals


The provisional patent application is a vital first step for inventors seeking to secure intellectual property rights.

Yet, many inventors often underestimate the complexities involved and make mistakes that could jeopardize their patents later.

This blog post aims to educate you on the top mistakes inventors make with their provisional patent applications and how to avoid them.

Our software tool, Patent Pending Made Simple, uses AI to help you avoid these mistakes, and helps you write a high-quality provisional patent application without relying on expensive lawyers.

The Importance of Provisional Patent Applications

Before diving into common mistakes, let's understand why provisional patent applications are essential. These applications establish an early filing date for your invention, offer 12 months to develop the invention further, and allow you to use the term "Patent Pending."

The United States Patent and Trademark Office (USPTO) provides a comprehensive guide on what provisional patent applications are and why they're beneficial ([USPTO](https://www.uspto.gov/patents/basics/types/provisional-app)). Despite the apparent simplicity, many inventors err in their provisional patent application processes. Here are some common mistakes.

Insufficient Disclosure

A provisional patent application's primary purpose is to establish a filing date and adequately disclose the invention. Failure to disclose your invention in detail can lead to problems later on when claiming priority ([USPTO](https://www.uspto.gov/web/offices/pac/mpep/s201.html)). For example, an incomplete or vague description can make it difficult to claim priority later.

Lack of Detail

Often, inventors do not furnish enough details about the invention. A provisional application should be as detailed as possible, including specifications, diagrams, and any other information that helps to explain the invention. Some people skimp on the details, thinking they can add them later. But a lack of details could make it difficult to transition to a non-provisional application later ([Harvard Business Review](https://hbr.org/2012/06/the-provisional-patent-a-first)).

Not Describing Alternative Embodiments:

Inventors sometimes describe only a single embodiment of the invention. Neglecting to cover alternatives can limit the scope of protection.(https://www.uspto.gov/web/offices/pac/mpep/s601.html)).

Not Clearly Distinguishing Between Prior Art and the New Invention

The application should make it clear what is new in the invention as compared to existing solutions. Failure to do so can make it more difficult to argue for the novelty of the invention. ([American Bar Association](https://www.americanbar.org/groups/intellectual_property_law/resources/landslide/2020-21/july-august/preparing-defensible-patent-application/)).

Failure to Describe Best Mode

The "best mode," or the best method known to the inventor for practicing the invention, must be disclosed. Otherwise, the patent could later be invalidated. (USPTO: https://www.uspto.gov/web/offices/pac/mpep/s2165.html).

Using Patent Profanity

Terms like “Special,” “Peculiar,” “Superior," “Very Important,” have been held to limit the scope of the invention when it comes to prosecution history estoppel, and should be avoided (https://www.finnegan.com/en/insights/blogs/prosecution-first/watch-your-language-the-perils-of-patent-profanity-consideration-of-both-the-us-and-europe.html). Other times, identifying a component as “preferred,” can be misconstrued to mean that other components are optional. This can limit the scope of a future non-provisional application.

Procedural and Formal Mistakes

Incorrectly Labelling Figures and Reference Numerals

Consistency in labelling is crucial for clarity and a thorough understanding of the invention. Any inconsistency can lead to confusion and weaken the application.

Not Following USPTO Guidelines

From formatting to the sequence listing, the U.S. Patent and Trademark Office has specific guidelines that need to be followed.

Leaving Fields Blank on Forms

Missing information on official forms can result in delays or, in some cases, a failure to secure the date of filing.

Waiting until the last minute to transition from a provisional to a non-provisional application can result in rushed, incomplete, or error-filled non-provisional applications ([FindLaw](https://smallbusiness.findlaw.com/intellectual-property/provisional-patent-applications-what-you-need-to-know.html)).

Ignoring Formal Requirements

Although provisional applications are less formal, they still have specific requirements like cover sheets and fees. Overlooking these can result in rejection (USPTO).

Cases Highlighting the Importance of Avoiding These Mistakes

Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co.

This case underscored the importance of having a thorough 'written description' in your application ([Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co., 598 F.3d 1336](https://casetext.com/case/ariad-pharms-v-eli-lilly-co-2)).

Novozymes A/S v. DuPont Nutrition Biosciences APS

The court examined whether the provisional application adequately supported the invention claimed in the later non-provisional application ([Novozymes A/S v. DuPont Nutrition Biosciences APS, 723 F.3d 1336](https://casetext.com/case/novozymes-as-v-dupont-nutrition-biosciences-aps-2)). In this case, claims in the non-provisional application were found not to be adequately supported by the provisional application, causing a loss of the earlier priority date.

Hologic, Inc. v. Minerva Surgical, Inc., 957 F.3d 1256 (Fed. Cir. 2020)

The court's decision discussed the relevance of the provisional patent application and its relationship to the patent-in-suit.

TorPharm Inc. v. Ranbaxy Pharmaceuticals, Inc., 336 F.3d 1322 (Fed. Cir. 2003)

This case illustrates the importance of ensuring that a non-provisional application is adequately supported by its provisional application.

St. Jude Medical, Cardiology Division, Inc. v. Volcano Corp., 749 F.3d 1373 (Fed. Cir. 2014)

This case highlights the importance of filing a new application if an invention changes substantially after filing a provisional application.

In re Packard, 751 F.3d 1307 (Fed. Cir. 2014)

While primarily about indefiniteness in patent claims, this case is a cautionary tale about the level of clarity required in patent applications, whether they are provisional or non-provisional.


A provisional patent application is a critical tool for securing intellectual property rights. Avoiding common mistakes ensures a smooth transition to a non-provisional application and mitigates risks down the line. Always consider hiring a patent attorney to guide you through this intricate process and ensure your application is both complete and accurate.