Just because a patent is granted does not mean that it will not be subjected to attempts to have one or more of its claims invalidated during the lifetime of the patent.   Such invalidation attempts by the defendants in a patent infringement lawsuit are not uncommon.  Grounds for invalidation include claim indefiniteness.  The public policy behind trying to prevent indefinite patent claims is that the public is entitled to know what the claim is really about. This blog discusses the recent opinion in University of Massachusetts, Carmel Laboratories, LLC  v. L’Oréal S.S., L’Oréal USA, Inc. by the Court of Appeals for the Federal Circuit (CAFC) where the court held that the patent claims were indefinite.  The opinion provides an excellent discussion of the type of analysis that goes into such a determination.

This is a long blog and hopefully instructive in its approach to explaining what went wrong for the patentee so that a similar mistake can be avoided by others during patent prosecution.

Some background information

A patent application examiner may reject a claim on the basis of indefiniteness.  Amendment of the claim by the applicant is an option to try to overcome the indefiniteness conclusion.  If an allegation of indefiniteness is made by the defendant during a patent infringement lawsuit, the court may engage in a process known as Claim Construction to determine what the claim is “really” saying or “not” saying.  In doing so, the court may refer to the patent’s specification to try and ascertain what the inventors were contemplating, how a particular word was defined, etc. and the prosecution history.  For a previous blog on the importance of the patent’s specification to claim construction, click here.   Generally, the court will rely on the plain reading of the claim.

The Questionable Claim in U Mass

A method for enhancing the condition of unbroken skin of a mammal by reducing one more of wrinkling, roughness, dryness, or laxity of the skin, without increasing dermal cell proliferation, the method comprising [1] topically applying to the skin a composition comprising a concentration of adenosine in [2] an amount effective to enhance the condition of the skin without increasing dermal cell proliferation, [3] wherein the adenosine concentration applied to the dermal cells is 10-4 to 10-7 M.

Can you see the problem with this claim?  First it says that a topical solution containing adenosine is applied to the skin but clause [1] does not recite the concentration of adenosine in this topical solution effective for achieving the result stated in clause [2].  Clause [3] with its “wherein” clause can be interpreted to mean that the amount of adenosine which ends up coming into contact with dermal cell falls in the specified range.  What is the actual adenosine concentration in the topical solution?  If clause [3] is intended to mean the resultant adenosine concentration in the dermis, was this concentration actually measured?  Furthermore, there are 2 objects intended for contact with the adenosine: the skin and the dermal cell.

The dermis is the skin layer under the outer epidermis layer.  Common sense would tell us that the topical solution would have to have an adenosine concentration greater than the amount of adenosine which ends up in a dermis cell for a number of physiological and structural skin reasons based on the topical solution’s absorption properties and the skin’s level of hydration and texture.   For example, the epidermis layer protects the dermis layer.  Anything intended for the dermis layer must first get through the epidermis layer. But what exactly is that concentration and why didn’t the claim just state “a topical solution having an adenosine concentration in the range of X-Y?”  Does clause [3] really refer to adenosine’s concentration in the dermis or is the clause the result of inartful drafting which has caused a big problem for the patent owner?

The CAFC’s Conclusion

The district court had relied on subjective determination precedent to conclude that the claim was indefinite because of clause [2] which focused on the topical solution’s effectiveness: “Indeed, the determination of whether the skin is enhanced provides a paradigmatic example of indefiniteness. Beauty after all, is ‘in the eyes of the beholder.’ ”

The Federal Circuit decided claim construction de novo because of the district court’s wrong approach to finding indefiniteness.  Upon appeal to the CAFC, U Mass contended that the “concentration” in the wherein clause is the concentration of adenosine in the dermis after it has entered the dermis.  In other words, to overcome an indefiniteness finding, U Mass would have to establish exactly what the suspect wording actually meant because the wording was ambiguous and not clear on its face.

The CAFC concluded that the claim was ambiguous about what clause [3] referred to:  “We first conclude that the relevant claim language, especially when viewed in the context of the whole claim, is not plain on its face, much less plain in supporting U Mass’s interpretation of it.”  Slip opinion at 8.  The court went on to emphasize the U Mass’s view of clause [3] is referring to something that has no existence before the application – that it refers to an adenosine concentration of the dermal layer after the adenosine particles per unit of dermal layer, after the adenosine particles have suffused into the dermis and thus already come into contact with the dermal cells.  Slip opinion at 10.   Therefore, the claim cannot be definite.

After the district court’s construction, U Mass had retained an infringement expert to conduct various experiments to assess the concentration as moles of applied adenosine in the dermis over liters of the dermis to “come up” with numbers within the range specified in the claim.  The CAFC emphasized that the expert’s methodology actually revealed an interpretation that would call for a rewrite of the wherein clause to say something like “wherein the adenosine permeating to the dermal layer results in a concentration of adenosine in the dermal layer of 10-4 to 10-7 M.   As such, the need for a departure from the natural meaning confirmed that U Mass’s asserted meaning is not plain.  Slip opinion at 10.

Next the court looked to the specification to see if it supported U Mass’s claim construction.  It did not.  Tellingly, the disclosure never implied that the invention included measuring adenosine concentrations beneath the skin surface after topical application. “U Mass has not shown that, even in this context, the specification makes clear that the inventors contemplated the adenosine concentration after exposure to the cells, rather than in a solution before application in the cells.”  Id. at 12.

The court also looked at the prosecution history, emphasizing that the histories resolve the ambiguity surrounding the meaning of “the adenosine concentration applied to the dermal cells” in the wherein clause. As with most patent applications, the prosecution history involved amendments to the original claims.  To overcome a prior-art rejection, U Mass imported a previous dependent claim which had only referred to an adenosine concentration with no mention of dermal cells into the preceding independent claim to create the problematic claim which now included the wording: formal “wherein the adenosine concentration applied to the dermal cells is …..” Slip opinion at 13.

The accompanying remarks made by the applicant are inconsistent with the “new wording” because they stated: “All [claims] are based on the application of certain concentrations of adenosine to the skin to achieve certain results.”   The applicants also stated that the amendment included no new matter suggesting that the invention was still and always was the topical solution at the specified concentration.  The new wording changed the scope and resulted in an indefinite claim. Interestingly, the examiner made the following comment in writing after accepting the amendment:  “the [i]nstant claims are directed to a method of enhancing the condition of unbroken skin . . . where the method comprises administering adenosine at a concentration of 10-4 M to 10-7 M, to the skin.” Slip opinion at 13.

According to the CAFC, U Mass’s amendments and comments clearly conveyed that U Mass had never veered from its pre-amendment reliance on the adenosine composition in the topical solution which had resulted in its two patents.  During prosecution, no mention had ever been of the materially different, unexplained notion of an adenosine concentration being determined after contact with the object (the dermis) of the topical solution.   Slip opinion at 14.   Even in its response to the examiner’s reasons for allowance, the applicants never communicated a disagreement with the examiner’s clear statement of what the language meant.

The CAFC reversed the district court’s claim construction of the wherein clause and vacated the court’s subsequent summary-judgement determination.  The case has been remanded for further proceedings consistent with the opinion.

Commentator’s Comments

This is a situation which seemingly could have been avoided.  The claims at issue in two related patents were not complicated.  The examiner made very clear that the adenosine was applied to the skin at the concentration range specified but somehow the claims ended up stating that the adenosine was applied to the dermal cells.   It is not clear why U Mass changed the wording in the amendment. Sloppy drafting?  Not carefully reading the new independent claims as whole?  Why didn’t the examiner mention anything about an incongruity between the amended claim and what the concentration range was referring to.  A few simple word changes could have resolved the ambiguity.

Patent prosecution can be a long, tedious process.  This case is a good lesson on how every aspect of the prosecution process must be monitored and the documents read and reread by both the patent attorney and the inventors.  An issued patent is in no way a guarantee that the patent will withstand scrutiny if push comes to shove in a court of law.   And if an amendment is made, make sure that it’s supported by the specification.   Remember, no new matter can be introduced in an amended specification.




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Posted in Uncategorized on July 31,2022 09:07 PM
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