Do you need a prototype in order to register a patent? A patent gives the patent owner exclusive rights to make, sell, or license the invention defined in it.

Do You Need a Prototype to Patent a New Invention?

Many inventors wonder if they need a working prototype before patenting an invention. The simple answer is “no.” A prototype is not a part of the legal requirements prior to filing a patent application with the U.S. Patent and Trademark Office (USPTO).

While prototypes can be valuable in developing your invention, they can also be costly. Developing a costly prototype is not required and in some situations may actually not be feasible. If a prototype of a new product can be constructed without spending a lot of money, then prototyping your invention can be a very good first step in the invention process.

Do you have questions about your new invention?  Call us at Verna Law, P.C., where we provide intellectual property legal services, at 914-908-6757 or send an e-mail to

Balancing the Benefits and Costs of Prototyping

To determine if creating a prototype of your invention is a good idea, you need to consider both the costs and benefits. If the costs are too great, then you should consider an alternative path. Below are the benefits and costs of prototyping:

Benefits of Prototyping

  1. Work out any potential design problems: Prototyping allows you to identify and solve design issues early in the product development process.
  2. Identify alternative solutions: Creating a prototype can reveal alternative ways to achieve your invention’s goals.
  3. Marketing tool: A prototype can be useful in marketing the invention to third parties, such as investors or potential licensees.

Costs of Prototyping

  1. Unnecessary expense: If you are only licensing your patent rights, the expense of prototyping may not be justified.
  2. Delays the invention process: Prototyping can add significant time to the development process.
  3. Time and energy: Developing a prototype requires time and energy that might not be necessary for the patent process.

When You Should Prototype Your Invention

There are situations when you should consider prototyping your invention before filing a patent application:

  1. Affordable and quick development: If a prototype will cost less than $1,000 and can be developed quickly, it might be worth the investment.
  2. Illustrating basic functions: If a prototype is needed to demonstrate the basic functions of your invention, it can be helpful.
  3. Uncertainty about design: If you are unsure if your product design will work, a prototype can provide valuable insights.

When You Should Not Prototype Your Invention

There are also situations when you should consider not prototyping your invention before filing a patent application:

  1. Simple design and no manufacturing intent: If you do not intend to manufacture and the product design is simple, a prototype may not be necessary.
  2. High prototype development costs: If developing a prototype would be expensive and you do not intend to manufacture, it may not be worth the cost.
  3. Licensing only: If you intend to only license your patent rights and the technology does not require a prototype to be understood, skipping the prototype is advisable.
  4. Prior public disclosure: If you have a prior public disclosure of your invention, you need to file a patent application before the one-year anniversary of your first public disclosure in the United States.
  5. Prohibitive costs: If the expense of creating a prototype would prevent you from pursuing your invention further, it is better to focus on the patent application first.

Prototyping vs. Not Prototyping

Ultimately, deciding whether to prototype your invention comes down to weighing the time and money required. Some inventors believe that prototyping is a crucial first step, while others view it as an unnecessary expense if you intend to license your patent rights. Balancing the benefits and costs of prototyping your idea is essential before hiring a prototype developer.

A prototype is not required to obtain a U.S. patent. However, assuming the prototype is kept confidential and there is no offer for sale, sale, public use, or other problematic activity before filing a complete and timely patent application, it may be helpful for various reasons to prepare a prototype. Generally, an inventor has a one-year grace period from their first disclosure to file a U.S. patent application, but many foreign countries do not provide any grace period, so keeping an invention and prototype confidential prior to filing is important to preserve any possible patent rights.

A prototype can help a registered patent attorney or patent agent better understand your invention and prepare a more robust patent application. It can also aid in preparing both a design patent application (for appearance) and a utility patent application (for function). For design patents, in particular, having an actual prototype can help ensure accurate and compliant drawings.  A prototype can help with a patent search in giving as much detail as possible to your patent professionals..

If you can describe your invention in sufficient detail for someone skilled in the field to practice it without a prototype, you should consider filing a patent application as soon as possible. This can secure your priority date and protect your invention against prior filings by others.


Further Considerations

  • Patent Specification Requirements: Every patent application must include a specification that explains the invention in sufficient detail for someone skilled in the field to practice it.
  • Controller’s Requests: In some cases, the patent office may request a model or sample illustrating the invention. This would only be required before the patent is granted, giving you time to create such a model or sample after filing the application.
  • First to File: Most patent systems, including the United States and India, operate on a ‘first to file’ basis rather than ‘first to invent,’ emphasizing the importance of filing as soon as possible.  This means choosing between a provisional application and non-provisional patent applications.  

In conclusion, while prototyping can be beneficial, it is not mandatory for filing a patent application. Inventors should carefully consider their specific circumstances and the costs and benefits involved before deciding whether to develop a prototype.


Here is the transcription of our video blog:

Hi, I’m Anthony Verna, managing partner, Verna Law, P.C. We focus on intellectual property and advertising law. You can find us at Now, let’s get to the meat of this.

Do I need a model or prototype before I can file a patent?


It’s one of the most misunderstood aspects of patent law: you do not need a model or a prototype to file for a patent application. Instead, you only need to have enough information in order to be able to explain your invention to someone, such as a manufacturer, that is capable of making it. As a rule of thumb, if you’re able to explain how to make your invention or how your invention works, then you should be able to file for a patent application. But – that’s one of the tricky parts here let’s get to from something to say theoretical to, well, what happens in real life.

If somebody comes to our practice and says, “I have a great invention! It’s a transporter beam!” and you’re not really able to describe how you’re going to take molecules of people, turn them into, you know, some other matter. And then, you know, deposit the person safely on the other side. Well, it’s not really going to work all that well, but again, that goes back to the practical part of this.

You have to be able to describe the invention, make sure your invention is new, novel, make sure it’s not obvious, absolutely.

Make sure that you’re able to describe it so that those who have the capability to make it can make it. You don’t need a model. You don’t need a prototype, but you have to have the ability to describe it fully. Without that description, your patent application will just never be able to go to fruition.

I’m Anthony Verna, managing partner of Verna law. Again, we focus on intellectual property, patents, trademarks, copyrights, domain names, and advertising law visit us at We’ll see you here next week.


Case studies:


  • Minerva Surgical, Inc. (Plaintiff-Appellant) vs. Hologic, Inc. and Cytyc Surgical Products, LLC (Defendants-Appellees)
  • Court: United States Court of Appeals for the Federal Circuit
  • Decision Date: August 11, 2020

Here is a case all about showing a prototype in public and the drawbacks of doing so if the product is not ready to go through the patenting process.

The case of Minerva Surgical, Inc. v. Hologic, Inc. et al. involved Minerva’s patent for a gynecologic device used in “endometrial ablation.” The United States Court of Appeals for the Federal Circuit affirmed a lower court’s ruling that invalidated Minerva’s patent based on the public use bar.

Minerva had displayed a prototype of its device at an industry expo more than one year before filing the patent. The court found that this display constituted a public use of the invention, which can invalidate a patent under the pre-America Invents Act (AIA) version of the patent statute if the invention is in public use more than one year before the patent application date.

Minerva argued that the display at the expo did not qualify as a public use for several reasons, including that it merely displayed the device, there was no disclosure of the invention because the device lacked a key claim limitation, and the invention was not ready for patenting as Minerva was still improving the technology at the time.

The Federal Circuit rejected these arguments, noting that the expo was a significant industry event open to the public, and Minerva had showcased the device to potential investors and physicians. The court found that the device was fully functional and disclosed the key features of the patent claims. Additionally, Minerva had reduced the invention to practice and had enabling documentation describing the invention at the time of the expo.

The court’s decision serves as a cautionary reminder for inventors and companies to be aware of the risks of showcasing new technology at public events before securing patent protection, as such actions could invalidate their patents under the public use bar.


Priority Dates are Affected by Prototypes

In NFC Tech v. Matal (Fed. Cir. 2017), the Federal Circuit reviewed a decision by the Patent Trial and Appeal Board (PTAB) regarding NFC Tech’s patent application. The PTAB had rejected NFC Tech’s priority claim to an earlier French patent application, which would have given NFC Tech an earlier filing date for its U.S. patent application.

NFC Tech had argued that it had reduced the invention to practice before the filing date of a key prior art reference, thus entitling it to the earlier priority date. The PTAB, however, found that NFC Tech had not shown that its inventor, Charrat, had actually reduced the invention to practice.

On appeal, the Federal Circuit reversed the PTAB’s decision. The court found that NFC Tech had provided sufficient evidence to establish that Charrat had conceived of the invention and communicated that conception to a third party who built a prototype embodying the invention. The court also found that the PTAB had improperly discounted certain evidence, such as a data sheet with Charrat’s initials, which supported NFC Tech’s position.

Overall, the Federal Circuit held that NFC Tech had adequately demonstrated that Charrat had conceived of the invention and had communicated that conception to others, thus entitling NFC Tech to the earlier priority date for its patent application.


Case summary:  Blue Gentian, LLC, National Express, Inc., Telebrands Corporation v. Tristar Products, Inc.2021-2316, 2021-2317

Legal Issues Involved:

  1. Patent Validity and On-Sale Bar:

    • 35 U.S.C. § 102(b): The court examined whether the patents in question were invalid due to the on-sale bar. This statute precludes patentability if the invention was on sale more than one year prior to the patent application filing date.
    • Public Disclosure of Prototypes: The central issue was whether the prototypes of the patented invention were disclosed to the public before the critical date. The court needed to determine if these disclosures constituted a public use or sale that would invalidate the patents.
  2. Inventorship and Derivation:

    • The case involved questions about the proper inventorship of the patents. The appellants argued that the named inventors on the patents were not the true inventors and that the invention was derived from someone else, which would render the patents invalid.
    • 35 U.S.C. § 256: This section addresses correction of inventorship and whether an error occurred in naming the inventors.
  3. Claim Construction:

    • The court analyzed the construction of certain patent claims. Proper claim construction is crucial because it defines the scope of the patent rights and determines whether the accused products infringe the patents.
    • Markman v. Westview Instruments, Inc.: This landmark case established that claim construction is a matter of law for the court to decide.
  4. Infringement:

    • Literal Infringement: The court evaluated whether the accused products literally infringed the patent claims as properly construed.
    • Doctrine of Equivalents: The court also considered whether the accused products infringed under the doctrine of equivalents, which allows for a finding of infringement even if the products do not literally infringe the claims, as long as they perform substantially the same function in substantially the same way to achieve substantially the same result.
  5. Prior Art and Obviousness:

    • 35 U.S.C. § 103: The court assessed whether the patented invention was obvious in light of the prior art. If the invention is deemed obvious, it cannot be patented.
    • The examination involved comparing the patented invention to prior art references and determining whether the differences would have been obvious to a person of ordinary skill in the art at the time of the invention.
  6. Commercial Success and Secondary Considerations:

    • The appellants argued that the commercial success of their products, along with other secondary considerations such as long-felt but unmet needs, supported the non-obviousness of the patented invention.
    • Graham v. John Deere Co.: This case established the framework for considering secondary considerations in the obviousness analysis.


The Federal Circuit’s decision involved a detailed analysis of these legal issues, ultimately determining the validity and enforceability of the patents and whether the defendant’s products infringed those patents. The role of prototypes and their disclosure was a key factor in the court’s analysis, impacting the resolution of the on-sale bar and public disclosure issues.


Other Protection Mechanisms

Consider keeping the invention a trade secret – usually done with a non-disclosure agreement with any contractors.  The confidential information is not public unlike the disclosures made for a new patent.

Do you have questions about your new invention?  Call us at Verna Law, P.C. at 914-908-6757 or send an e-mail to