Unit 1, Patents, Part 3

2.2 Inventive Step and Non Obviousness

Principle

The second fundamental requirement for patentability is that the invention must involve an “inventive step” or be “non-obvious.” This requirement stipulates that the invention must not have been obvious to a “person skilled in the art” (a concept we will explore further shortly) or, in U.S. patent law terminology, a person of “ordinary skill in the art.

At its core, obviousness means that if an individual with average technical skill in the relevant scientific or engineering field could readily combine existing pieces of knowledge to arrive at the claimed invention, then that invention is not considered patentable.

Crucially, non-obviousness differs from novelty in a significant way: an invention may be deemed obvious even if it is not explicitly and entirely disclosed in a single prior art reference. A patent examiner may conclude that an invention is obvious by combining information from multiple prior art references.

The underlying rationale for the non-obviousness requirement is to ensure that patents are granted only for inventions that represent a substantial improvement over the existing state of the art and offer a meaningful contribution to technological advancement.

When assessing inventive step, the claimed invention as a whole must be considered. This means the invention’s features and their combined technical effect should be evaluated, rather than examining each element in isolation.

Example: Obviousness in Pharmaceutical Patenting

A notable case illustrating the concept of obviousness involved the invalidation of a patent held by Merck for the blockbuster osteoporosis drug Fosamax, specifically its once-weekly formulation. The patent was revoked because prior art rendered the claimed invention obvious.

Approximately one year before Merck filed its patent application, two articles were published in a prominent pharmaceutical journal discussing osteoporosis treatment. These articles proposed using a once-weekly dosage of a bisphosphonate as an alternative to the then-standard daily administration. The key insight was that a weekly regimen could significantly alleviate the gastrointestinal side effects associated with daily dosing.

Merck’s patent application sought to protect this specific once-weekly dosage regimen* which was approximately seven times the equivalent daily dose.

Despite the patent initially being granted, a subsequent legal review found it to be invalid. The reason cited was that the invention was “obvious” in light of the previously published articles, which had already disclosed the core concept of a weekly dosage for bisphosphonates to treat osteoporosis. The court determined that a person of ordinary skill in the pharmaceutical field would have found it obvious to adjust the daily dosage to a weekly regimen to achieve the identified patient benefits.

A Person Skilled in the Art, Defining the Hypothetical Expert

The concept of a “person skilled in the art” (or “person of ordinary skill in the art” in U.S. patent law) is a crucial, albeit hypothetical, construct used in patentability assessments. This individual is presumed to possess several key attributes:

Access to Prior Art: They are assumed to have access to all publicly available information that constitutes prior art relevant to the field of the invention.
Technical Understanding: They possess the ability to understand all technical matters within the relevant scientific or technical domain.
General Knowledge and Skills: They are endowed with the common general knowledge and ordinary practical skills typical of practitioners in that specific field.
Routine Experimentation: They have access to the normal means and capacity for routine experimentation, enabling them to clarify ambiguities in existing technologies or confirm known principles.

What this hypothetical person is NOT expected to do:

Inventive Capabilities: This person is not expected to possess inventive capabilities beyond the ability to apply standard logic and reasoning to combine existing knowledge.
Inventive Imagination: They are not required to exercise inventive imagination, discover entirely new knowledge, or significantly advance the state of the art. Their role is to assess whether the claimed invention could have been readily conceived based on existing information.

Team of Specialists:

In certain complex technological fields, the “person skilled in the art” may be conceptualized as a team or group of specialists. For instance, an invention in the field of bioinformatics within medicine might involve a presumed team comprising experts from biotechnology, medicine, and information technology, each contributing their specialized knowledge.

Level of Skill:

The level of skill and knowledge attributed to this hypothetical person varies depending on the specific technological field. It generally falls between the knowledge of an average practitioner and the expertise of a leading specialist. The standard is that of an ordinary, duly qualified practitioner in the relevant field.

Analysis for Determining Inventive Step and Non Obviousness

Different patent jurisdictions employ distinct methodologies to assess whether an invention meets the inventive step or non-obviousness requirement.

1. United States Approach:

In the U.S., the determination of obviousness typically follows a structured, multi-step analysis:

Scope and Content of the Prior Art: Identifying and understanding all relevant prior art.
Differences between Prior Art and the Claimed Invention: Clearly delineating what is new in the claimed invention compared to the prior art.
Level of Skill in the Pertinent Art: Assessing the capabilities and knowledge of the hypothetical person skilled in the art.

2. European Patent Office (EPO) Approach (Problem-Solution Approach):

Many other jurisdictions, including those following the practice of the European Patent Office, utilize a framework known as the “problem-solution approach.” This method involves the following steps:

Determine the Closest Prior Art: Identify the single most relevant piece of prior art to the claimed invention.
Establish Distinguishing Features: Identify the specific technical features of the claimed invention that distinguish it from the closest prior art.
Formulate the Objective Technical Problem: Based on the distinguishing features and the closest prior art, define the technical problem that the invention aims to solve. This formulation must be objective and should consider the technical effect achieved by the invention.
Assess Obviousness: Consider whether the claimed invention, starting from the closest prior art and the formulated objective technical problem, would have been obvious to a person skilled in the art. This involves determining whether the skilled person, faced with the problem, would have been motivated to modify the closest prior art to arrive at the claimed solution.

Identifying Differences: The Core of Prior Art Comparison

To determine whether an invention is novel or obvious, a patent examiner compares the claimed invention with the existing body of prior art. This involves:

Detecting Similarities and Differences: The examiner carefully analyzes both the prior art references and the claimed invention to identify precise similarities and differences.
Comparing Processes: If both the claimed invention and a prior art reference describe a method or process (e.g., for manufacturing a compound), the examiner compares the specific steps involved to determine whether they are distinct.
Comparing Structures: For inventions such as chemical compounds with defined structures, the examiner compares the claimed chemical structure with those disclosed in the prior art to identify differences in their constituent components.

Consequences of Prior Art Disclosure:

Destruction of Novelty: If a prior art reference discloses all features of the claimed invention, the examiner will conclude that the invention lacks novelty.
Finding of Obviousness: If a prior art reference closely resembles the claimed invention, such that a person skilled in the art could readily arrive at the invention, the examiner may deem the invention “obvious.” This is particularly likely if the examiner can combine that reference with other prior art references that, together, disclose all features of the claimed invention.

(For a more in-depth discussion on the procedures for rejecting or allowing claims during patent prosecution, please refer to Module IX.)

Avoiding Impermissible Hindsight Analysis

A critical challenge in assessing obviousness is the risk of “hindsight analysis” (also known as “ex post facto analysis”). Once an invention has been conceived and disclosed, it may appear more obvious than it actually was at the relevant date. This is because knowledge of the invention can unconsciously influence the assessment of its obviousness. Therefore, patent examiners and courts must exercise care to avoid applying hindsight when determining whether a claimed invention was obvious at the relevant time.

Teaching Away: A Shield Against Obviousness

In the context of determining non-obviousness, if a prior art reference explicitly discourages or advises against using a particular element or approach that is central to the claimed invention, that reference may not be relied upon to demonstrate obviousness. This principle is known as “teaching away”.

Example: Teaching Away in Electroplating Solutions

Consider the following scenario involving copper electroplating solutions:

Prior Art Reference X Discloses:

(i) An alkaline solution of copper sulfate;
(ii) A concentrated acid of 30–50 grams per liter, excluding sulfuric acid; and
(iii) An aqueous solution of a pH-modifying substrate sufficient to adjust the pH to 3.5–5.0.

Inventor A's Invention:

(i) An alkaline solution of copper sulfate;
(ii) Sulfuric acid of 10–20 grams per liter; and
(iii) An aqueous solution of a pH-modifying substrate sufficient to adjust the pH to 3.5–5.0.

In this example, Prior Art Reference X explicitly excludes sulfuric acid as the acid component (element ii). Inventor A’s invention, however, specifically uses sulfuric acid within a defined range. Because the prior art teaches away from using sulfuric acid, it cannot be used to demonstrate that Inventor A’s invention would have been obvious. The exclusion in the prior art suggests that a person skilled in the art would not have been motivated to modify the prior art in the manner claimed by Inventor A.

Secondary Considerations: Supporting Evidence for Non-Obviousness In addition to the primary analysis of prior art and the hypothetical “person skilled in the art,” patent examiners and courts may consider secondary factors when assessing the non-obviousness of an invention. These factors provide supplementary evidence that can support a finding of non-obviousness, especially when the primary analysis may suggest obviousness.

Key secondary considerations include:

Solving a Long-Standing Problem: If the invention addresses a problem that has persisted in the field for a considerable period without a satisfactory solution, this may indicate a degree of inventiveness.
Overcoming the Failure of Others: Evidence that others have previously attempted to solve the problem addressed by the invention but failed may indicate that the invention was not readily achievable or obvious.
Commercial Success: In some jurisdictions, evidence that the invention has achieved significant commercial success may serve as an indicator of non-obviousness. This success suggests that the invention provides a valuable solution that the market recognizes and adopts, which might not have occurred if the invention were merely an obvious adaptation of existing knowledge.

Important Caveat:
It is important to note that secondary considerations are generally subordinate to the primary analysis. If the primary analysis clearly establishes that an invention is obvious in light of the prior art, the presence of secondary factors will typically not be sufficient to overcome an objection of obviousness. These factors are most influential when the primary analysis presents a close or borderline case.

The Secretariat of WIPO assumes no liability or responsibility with regard to the transformation or translation of the original content. World Intellectual Property Organization (WIPO) (2023). WIPO Patent Drafting Manual, Second edition. Geneva: WIPO. DOI: 10.34667/tind.44657