General Patent Requirements
Some ideas and inventions will not qualify for any of the three patent options, no matter how great the idea or invention may be. For example, illegal ideas or products, surgical methods and procedures, math formulas, laws of nature, newly discovered natural elements or substances and theories, no matter how brilliant, will never qualify for a patent. To qualify generally for a patent, an idea must be novel, non-obvious and useful. Ultimately, though, the subject of what is and is not a patentable idea has been, and likely will continue to be, the subject of numerous lawsuits.
A utility patent applies to an idea that either is or produces a useful, tangible end-product. Common examples of inventions that qualify for a utility patent include end-products such as a cellphone antenna, a manufacturing machine such as a new laser drill or a new chemical composition such as soap that causes your hands to glow in the dark. A utility patent grants the patent holder the exclusive right to use, produce and distribute the patented idea for 20 years.
A design patent, while sometimes difficult to distinguish from a utility patent, covers ideas that are useful but not necessarily functional. For example, a golf club design that improves the way the club hits the golf ball would qualify for a utility patent, while a design that merely enhances the look of the club but does not affect the way the club hits the ball, would qualify for a design patent. A design patent grants the patent holder the same exclusivity rights as a utility patent, but the design patent lasts for only 14 years.
A plant patent is the least common type of patent, as it applies only to anyone who invents or discovers and asexually reproduces any distinct and new variety of plant. Like a utility patent, the plant patent grants exclusive rights for 20 years. However, the key difference with a plant patent is that, unlike with design and utility patents, the invention does not have to be useful. Instead, the patent applicant need only show that the idea is novel and non-obvious. For instance, a genetically altered form of house plant may qualify for a plant patent, even though the house plant is not necessarily useful.