Insight
February 22, 2022

A Primer on Patenting Ranges — All About "About"

In our previous Goodwin Insights post on “Patenting Ranges,” we discussed how Life Sciences companies can successfully patent concentrations of a drug product in a clinical formulation, or patent doses of a drug product administered to a patient. Here, we discuss the significance of the word “about” in Patenting Ranges. 

WHAT ABOUT “ABOUT”?

The word “about” before a specific point in a range (e.g., a formulation comprising about 0.001% (w/w) of an excipient) in a patent’s claim suggests that an inventor desired an average of the specific point that included a margin of error, or a range falling withing the word “about” as defined by the inventor in the patent. 

Inconsistent use of “about”, e.g., if not used in a claim (e.g., a formulation comprising 0.001% (w/w) of an excipient) but used in the context of other ranges or specific points in other parts of the patent, could be suggestive that the inventor understood when to use and when not to use “about.” Such inconsistent use of the word “about,” when absent in a claim of the patent but present elsewhere in the patent, could be interpreted that the inventor wanted only to patent the specific point but not a range falling within, and certainly not outside, the minor variations in a range. 

WHY “ABOUT” MATTERS

Between “about 0.001% (w/w)” and “0.001% (w/w),” in the example above, the narrower meaning of the claim would be one in which the drug formulation has the exactly the specified amount – 0.001% (w/w). And when faced with a decision to interpret a claim between the broader and the narrower meanings, courts usually will go with the narrower meaning (i.e., the exact amount of 0.001% (w/w), without including any variation outside the expected range of experimental variation) – assuming that the facts (experimental details and/or scientific rationale) support that narrower interpretation. 

HOW TO AVOID INCONSISTENT INTERPRETATION OF A SPECIFIC POINT IN A RANGE?

Inconsistent use of the word “about” in a patent application can be easily remedied by consistently using the word before any specific point and within the range (e.g., a formulation comprising about 0.001% (w/w) of excipient 1, and about 0.01% – about 1% (w/w) of excipient 2). Alternatively, one may be consistent in never using the word “about” (e.g., a formulation comprising 0.001% (w/w) of excipient 1, and 0.01% – 1% (w/w) of excipient 2, in a patent in which the word “about” never appears in the context of the claimed excipients).

HOW ABOUT “LESS THAN” OR “MORE THAN”?

Pharmaceutical formulations may include a language such as: “1% (w/w) or less” or “0.1% (w/w) or more.” In such instances, use of the word “about” can have two significance: 

  • When claimed as “about 1% (w/w) or less” or “about 0.1% (w/w) or more,” depending on facts (i.e., data/scientific rationale), the range might be interpreted as inclusive of a margin of error around 1% or 0.1% (w/w), as described in the patent or commonly understood in the technology area. Essentially, in such circumstances, a copycat drug formulation within a margin of error (or even beyond, depending on how “about” is defined in the patent) of the 1% (w/w) of the excipient, for example, might be found to infringe the claim.
  • When claimed as “1% (w/w) or less” or “0.1% (w/w) or more,” depending on facts (i.e., data/scientific rationale), the range might be interpreted as exclusive of a margin of error around 1% (w/w) or 0.1% (w/w), as described in the patent or commonly understood in the technology area. Essentially, in such circumstances, a copycat drug formulation having slightly above an expected minor experimental variation of the claimed 1% of the excipient – i.e., not exactly at 1% (w/w) of the excipient, for example, might be found to not infringe the claim.

HOW TO AVOID INCONSISTENCY ABOUT “ABOUT”?

  • Never use “about” anywhere in the application;
  • Use “about” always throughout the claims and the specification when describing a range and a specific point in a range;
  • If used, define “about” to be inclusive of a range outside the normal margin of experimental error;
  • Use “about” when amending a claimed range to a specific point:
    • About 0.01% – about 1% (w/w) of excipient 2” --> 
      • Amend as: “about 0.05% (w/w) of excipient 2”.
        • Do Not Amend to: “0.05% (w/w) of excipient 2”.
  • If facts (i.e., data/scientific rationale) support use of “about,” never submit a statement during prosecution in which the word “about” is absent in the context of the specific point within the range; and
  • If facts do not support, do not use “about” ever:
    • Courts might interpret the specific point to include a margin of error based on intrinsic record (e.g., 5% variation, if the intrinsic record would support such an interpretation).

CONCLUSION

All about “about” is either using or not using consistently, and never relying on facts or interpretation of another party (including the courts) of what the inventor intended to patent.