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Patent Law for Chemists:  A Tutorial

What Is A Patent?

• A granted U.S. patent gives the patentee the right to exclude others from making, using, selling, offering to sell, or importing into the U.S. the patented invention

• Parties who engage in these acts without the permission of the patentee during the term of the patent can be held liable for infringement

What Can Be Patented?

• A “utility patent” can be obtained for a process, machine, manufacture or composition of matter that is useful, novel, and non-obvious

• Other kinds of patents or patent-like protection include design patents for new, original and ornamental designs; plant patents for distinct, new varieties of plants that have been asexually reproduced; and plant variety protection certificates for sexually reproduced plants that are stable and clearly distinguishable from known varieties.

The Patent Instrument: A Written Description Concluding with Claims

The Patent Act, 35 U.S.C. § 112, states that:

“… the specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains … to make and use the same ….“

and

“… the specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.”

The requirement for definiteness, i.e. that the claim must particularly point out and distinctly claim the subject matter which the applicant regards as his invention, serves two critical functions:

• It allows examiners to determine whether the invention is patentable

• It informs the public of which technologies will infringe

Infringement Suit: The Process (Simplified)

• A patentee may file a civil suit in federal court in order to enjoin infringers (i.e., obtain a court order to stop the act of infringement) and obtain monetary remedies

• The court (i.e. judges) will first construe (interpret) the claims as a matter of law – Markman v. Westview Instruments, 52 F.3d 967 (Fed. Cir. 1995); 517 U.S. 370 (1996)

• A jury will then determine, as a question of fact, whether infringement of the correctly construed claims has occurred

• The accused infringer may assert invalidity for indefiniteness (i.e. insoluble ambiguity in the claims) as one defense

• Other possible defenses include invalidity for anticipation (i.e., lack of novelty) or obviousness, and unenforceability for inequitable conduct (e.g., by misleading the Patent & Trademark Office)

Note that any flaws in the patent are likely to come to light during the course of an infringement suit.  In fact, it is not unusual for the outcome of the suit to turn on such flaws. 

Claim Terms Generally Given Their Ordinary and Customary Meaning

Prior to July 2005, claim terms were interpreted by two diverse methods:

• Presume that the ordinary meaning, e.g. as provided by a dictionary or treatise, applies and then look to the intrinsic record (i.e., the specification and the prosecution history, if in evidence) to see if the patentee has used the term in a manner that is clearly inconsistent with this meaning -- Cf. Texas Digital Systems, Inc. v. Telegenix, Inc., 308 F.3d 1193 (Fed. Cir. 2002)

• Consider the ordinary and customary meaning to be that revealed by the context of the intrinsic record; consult extrinsic sources as needed in order to clarify any remaining ambiguity -- Cf. Alza Corp. v. Mylan Laboratories, 391 F.3d 1365 (Fed. Cir. 2004)

In July 2005, the Court of Appeals for the Federal Circuit reconsidered the case of Phillips v. AWH en banc (i.e., with all judges of the court participating, and with various interested parties invited to offer input) in order to resolve issues concerning the construction of patent claims, particularly:

• Should the courts look primarily to dictionaries and similar sources to interpret a claim term or to the patentee’s use of the term in the specification?

• If both sources are to be consulted, in what order?

The en banc Court prescribed the following hierarchy of references for interpretation of claim terms:

• the asserted claim

• the other claims

• the specification

• the prosecution history

• unbiased extrinsic evidence (e.g., technical and non-technical dictionaries; treatises)

• biased extrinsic evidence (e.g., expert testimony) 

Implications of Phillips v. AWH:  The Court's decision indicates that it is now more important than ever to ensure consistency between terms used in the claims and in the specification, and unambiguously elucidate the intended meaning and scope of these terms.  Furthermore, the specification should explicitly distinguish between, on the one hand, exemplary or optional features or embodiments and, on the other, required features or the invention as a whole.  Failure to make such distinctions clear may result in an unintended narrowing of the claims to encompass only the disclosed embodiments.

-- Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005)

Principles of Claim Interpretation (a.k.a. Claim Construction)

The general principles described below are applied in the interpretation of patent claims in the U.S. Federal Court system.  Having an understanding of these principles is helpful when writing patent applications.

• Claim terms are generally given their ordinary and customary meaning as would be understood by one of ordinary skill in the relevant art at the time of filing

• In order to interpret the claim, the court first consults the intrinsic evidence:

  • the claims

  • the remainder of the patent document

  • the prosecution history (if in evidence)

  • prior art cited in the prosecution history

• The court may also consult extrinsic evidence, i.e., dictionaries, encyclopedias, treatises

• Expert testimony is usually given little weight

• The patentee can be her own lexicographer, that is, define her own terms in a way that rebuts the ordinary and customary meaning

• Any such rebuttal of the ordinary and customary meaning may be explicit or implicit, but must be clear

• The patentee may, either purposefully or inadvertently, disavow or disclaim scope of coverage:

  “Where the general summary or description of the invention describes a feature of the invention … and criticizes other products … that lack that same feature, this operates as a clear disavowal of these other products (and processes using these products).” -- Astrazeneca AB v. Mutual Pharmaceutical Company, 384 F.3d 1333 (2004)

• Limitations must not be imported by the court from the specification into claims

• The court may try to maintain validity of a claim when resolving ambiguities (but this is not always possible!)

• The court may try to maintain inclusion of the preferred embodiment by a claim when resolving ambiguities (but this is not always possible!)

• It is generally assumed that claims should not be redundant, and that a dependent claim is narrower in scope than the independent claim from which it depends

• Describing “the invention” or the “preferred embodiment” has different implications than describing “an embodiment”

• The same term used in multiple claims is assumed to have the same meaning

• Use of two different terms in the claim(s) implies a different meaning for each

• All claim terms are assumed to have some meaning

• A claim cannot have different meanings at different times – time-sensitive words such as “normally”, “standard”, “conventional”, “traditional” are interpreted as of the effective filing date

• Transition words, e.g., “comprising”; “consisting of”; “consisting essentially of”; “including” have very specific meanings -- Manual of Patent Examining Procedure, 8th ed., rev. 5 § 2111.03 (2006)

• The transitional term "comprising", which is synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional, unrecited elements or method steps

• The transitional phrase "consisting of" excludes any element, step, or ingredient not specified in the claim.

• The transitional phrase "consisting essentially of" limits the scope of a claim to the specified materials or steps "and those that do not materially affect the basic and novel characteristic(s)" of the claimed invention. -- Manual of Patent Examining Procedure, 8th ed., rev. 5 § 2111.03 (2006)

• “Consisting of a” is singular; but “comprising a” may be plural

• A “Markush” claim – typically, “a member selected from the group consisting of A, B, and C” – is interpreted to represent a single member of the group, unless expressly indicated otherwise

• Special Case: Means-Plus-Function Claims

  • 35 U.S.C. §112 ¶6 states:

    “An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof . . . ”

    
    “. . . such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.”

  • Example of a Means-Plus-Function Claim:

    A sound system, comprising:

    • An amplifier

    • A pair of speakers

    • A means for delivering an electronic audio signal to said amplifier

    If the specification explains that a phonograph, a cassette deck and a CD player are all means for delivering an electronic audio signal to an amplifier, these items and their equivalents would be covered, but a radio receiver would not.

  • Using the word “means” in a claim element raises a rebuttable presumption that §112 ¶6 applies

  • A claim term in an apparatus claim that does not use the word “means” is rebuttably presumed to fall outside §112 ¶6

  • Another noun that lacks a well-understood structural meaning in the art may serve as an equivalent to the term “means” and thereby invoke §112 ¶6

  • Construction of Means-Plus-Function Claims (Cardiac Pacemakers v. St. Jude Medical, 296 F.3d 1106 (Fed. Cir. 2002):

    1. The claimed function is identified first

       • The function is limited to those recited in the claim language

       • The claim language is interpreted by ordinary principles of claim construction

       • Such functions are not to be broadened or narrowed beyond the claim language

       • Functions not recited in the means plus function claim, even if performed by the corresponding structure, are not to be included in the claim construction

    2. The corresponding structure that performs that function is determined

       • The specification must link or associate structure with the function

       • If there is no disclosed structure to perform the function, the claim is invalid

       • The “corresponding structure” must include all the structure that performs the recited function

       • However, just as functions that are not recited in the claim language are not to be included in the claim construction, neither are structural features that do not actually perform the recited function properly included

• Special case: Jepson claims

  • A “Jepson claim” defines an invention in two parts:

    • A preamble which recites the admitted prior art

    • An “improvement” clause which recites what the applicant regards as his invention

  • Example of a Jepson style claim:

  2. A method of providing gas assistance to a resin injection molding process of the type in which hot resin is injected into a mold, gas is injected into the mold to displace a portion of the resin in the mold, the resin cools, the gas is vented and the mold is opened to remove the molded part, a supply of stored gas is provided, the gas is injected into the mold to displace the resin in the mold cavity at a pressure that is at all times during the gas injection cycle substantially below the pressure of the stored gas supply, the improvement wherein, following the initial injection of the gas into the mold and prior to the venting of the gas from the mold, the gas pressure within the mold is selectively increased, decreased, or held substantially constant depending upon the particular requirements of the molding process. -- Epcon Gas Systems v. Bauer Compressors, 279 F.3d 1022 (Fed. Cir. 2002)

  • Implications of using a Jepson style claim:

    • The preamble unquestionably acts as a claim limitation

    • Any subject matter recited in the preamble presumptively constitutes prior art, even if it does not otherwise meet the criteria for prior art specified in 35 U.S.C. §102

    Thus, in the example above, all of the subject matter that precedes the phrase “the improvement wherein” is construed as a claim limitation and is rebuttably presumed to be prior art

    Patent offices, especially the European Patent Office, favor the use of Jepson claims because they explicitly identify prior art.  However, unless required by the patent office as a condition for allowance of a claim, inventors would be wise to avoid the use of Jepson style claims.

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Glossaries of Patent Law Terms -- Click on the links below

The 'Lectric Law Library's Legal Lexicon

U.S. Patent and Trademark Office Glossary of Terms

JOM Patent Glossary

Brown & Michaels Patent Glossary

NOLO Intellectual Property Law Glossary

Additional Resources

Principles Of Patent Law (Hornbook Series), R.E. Schechter and J.R. Thomas, West Group Publishing (2004), ISBN: 0314147519.

 

Organic Chemistry and Patents by Dr. Koen Van Aken.

 

What Every Chemist Should Know About Patents by Le-Nhung McLeland for the ACS Joint Board–Council Committee on Patents and Related Matters.

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