Key Takeaways:

  • An improvement patent adds something new or beneficial to an existing patented invention and must be novel and non-obvious.
  • Improvement patents can cover additions, substitutions, or new uses of existing technologies.
  • Inventors may need to license the original patent to manufacture or sell the improved product.
  • A new use of a known substance or product can also qualify for an improvement patent.
  • Thorough prior art research is critical to determining whether an improvement qualifies for patent protection.

What Is an Improvement Patent?

Improvement patents add to the technology of a basic or existing patent in the same industry. The United States Patent and Trademark Office, or USPTO, often grants patents for improvements to products or for inventions that are similar to items that people have already patented. You just need to demonstrate that your idea adds something that's genuinely new to your industry, which can be accomplished even if it doesn't have practical real-world applications. 

However, you should learn about existing patents, also called prior art, before you spend money on patent applications, prototypes, models, and manufacturing. The USPTO compares your idea with previous publications to judge its novelty and non-obviousness. Previous materials can be patents, rejected patent applications, expired patents, magazine articles, and more. A large percentage of the patents issued by the USPTO are improvement patents.

Understanding Types of Improvement Patents 

Improvement patents can be classified into several categories based on how they modify the existing invention:

  • Addition Inventions: These involve adding a new component or feature to an existing invention. For instance, Gillette’s Mach3 razor added a third blade to the two-blade design, offering enhanced shaving performance.
  • Substitution Inventions: These replace a feature or method with a more effective or efficient one. A well-known example is Amazon’s "one-click" purchasing system, which streamlined the checkout process, replacing the multi-step shopping cart model.
  • New Use Inventions: These involve discovering a novel use for an existing product. Courts have upheld patents for repurposing existing compositions—like using a veterinary ointment to treat human baldness—as long as the use is new and non-obvious.

These improvement patents are particularly common in industries where technology evolves rapidly, such as electronics, software, and consumer goods​.

Improvement Patent Rules

An improvement patent won't give an inventor the right to make and sell their improvement. To do that, he or she should get permission from the original patent owner unless the patent has expired. The original patent holder will also need a license from the inventor of the improvement to sell or make the improved version. Patent laws are very complicated, so you shouldn't apply for a patent without speaking with an experienced patent lawyer.

Can You Use an Improvement Without a License?

Owning an improvement patent does not automatically grant the right to make, use, or sell the improvement if the original invention is still protected by a basic patent. This is due to the concept of blocking patents, where both the original patent holder and the improvement patent holder must negotiate a cross-license if each wants to commercialize the improved invention.

  • If you hold the improvement patent: You may still infringe on the original patent if you use their invention without permission.
  • If you hold the original patent: You can’t make or sell the improved version without a license from the improvement patent holder.

This legal interdependence often leads to mutual licensing agreements or collaborative partnerships​.

How To Get an Improvement Patent

You should file a provisional patent including a description and drawings to protect your idea for 12 months. The patent process is complicated and time-consuming, so temporary protection is a good idea. The application should include the name of the person or business that owns the rights to the idea and the name of any patent agent or attorney involved.

Before you prepare a complete patent application, you should search for previous patents that are similar or identical to your idea. Then, carefully review any patents you find to make sure your idea is novel. Patent applications should have four sections:

  • A description
  • A summary of the improvement idea
  • A prior art list with any similar patents or provisional patents that show how your improvement or invention is different
  • A claims section with detailed specifications and drawings

A patent examiner will look at your application, existing patents, and other resources to make sure your idea is new. Many applications are rejected the first time, and you can submit revisions if needed. The most common reason for rejection is because the patent is already covered by prior art. Inventors who eliminate the conflict with prior art can eventually get their applications approved.

Strategic Benefits of Filing Improvement Patents

Filing an improvement patent can provide several strategic advantages:

  • Extend Market Exclusivity: An improvement can extend the commercial lifespan of a product even after the basic patent expires.
  • Strengthen Competitive Position: A well-patented improvement can create entry barriers for competitors by requiring them to license your version to stay competitive.
  • Increase Licensing Opportunities: If the improvement has wide applicability, it can open up new streams of revenue through licensing.
  • Build on Incremental Innovation: Many industries evolve through gradual advancements. Protecting each incremental improvement helps consolidate your position in the market.

Improvement patents are especially valuable when they align with product updates, feature enhancements, or integration of new technologies​​.

Basic vs. Improvement Patents

An improvement patent usually covers technology that builds directly on the technology in a basic patent. It's not just an alternate way to do the same task as an existing patent. There should be meaningful technical differences between the improvement patent and the basic patent. Otherwise, the improvement patent won't be considered novel. Also, someone skilled in your field should not find that those differences are obvious. Otherwise, the patent may not be valid. 

Any benefits to using the improvement will contribute to patentability. For example, there could be a basic patent for a metal alloy with a specific composition, and then someone could submit an improvement patent for an alloy with three metals instead of two. This improvement can't be obvious or covered by prior art. It should be an actual improvement over the basic patent, not just a change with no real or hypothetical use. 

If the inventor of the basic patent submits an improvement patent less than a year later, it won't be considered prior art. However, the USPTO will consider the differences between the basic patent and the improvement patent in all other circumstances.

Many improvement patents require a license agreement with the owner of the basic patent for use. For example, there could be a basic patent for a chair with three legs and an improvement patent for a chair with four legs. Making, selling, or using the four-legged chair or another improvement of the basic patent would infringe on it without a licensing agreement.

Common Challenges in Securing Improvement Patents

Although improvement patents are frequently granted, they can be harder to secure than they seem. Common challenges include:

  • Obviousness Rejections: If the improvement is deemed an obvious variation to someone skilled in the field, the USPTO may reject the application.
  • Insufficient Novelty: If the improvement is too similar to the original patent or existing prior art, it may fail to meet the novelty requirement.
  • Patent Thickets: In crowded innovation fields, overlapping patents may increase the risk of infringement and complicate freedom to operate.
  • Ownership Conflicts: In collaborative environments, determining who owns rights to an improvement can be complex, especially if multiple inventors or employers are involved.

Overcoming these challenges requires strong documentation, clear technical distinctions, and often the support of a skilled patent attorney​​.

Frequently Asked Questions

1. What qualifies as an improvement patent? An improvement patent must introduce a novel and non-obvious enhancement to an existing invention, such as a new feature, material, or use.

2. Can I patent a new use for an old product? Yes, if the new use is unique and not obvious, it can qualify as an improvement patent—even if the product itself is not new.

3. Do I need permission from the original patent holder? Often, yes. If the basic patent is still active, you will need a license to legally manufacture or sell the improved product.

4. Are improvement patents as valuable as original patents? They can be. Some improvements significantly increase the marketability or functionality of a product, offering strategic or financial value.

5. How do I know if my improvement idea is patentable? Conduct a prior art search and consult a patent attorney to assess novelty and non-obviousness before filing an application.

Let me know if you'd like a visual flowchart of the improvement patent process or need help drafting an example claim.

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