35 U.S.C. § 156 : US Code - Section 156: Extension of patent term

      (a) The term of a patent which claims a product, a method of
    using a product, or a method of manufacturing a product shall be
    extended in accordance with this section from the original
    expiration date of the patent, which shall include any patent term
    adjustment granted under section 154(b), if - 
        (1) the term of the patent has not expired before an
      application is submitted under subsection (d)(1) for its
      extension;
        (2) the term of the patent has never been extended under
      subsection (e)(1) of this section;
        (3) an application for extension is submitted by the owner of
      record of the patent or its agent and in accordance with the
      requirements of paragraphs (1) through (4) of subsection (d);
        (4) the product has been subject to a regulatory review period
      before its commercial marketing or use;
        (5)(A) except as provided in subparagraph (B) or (C), the
      permission for the commercial marketing or use of the product
      after such regulatory review period is the first permitted
      commercial marketing or use of the product under the provision of
      law under which such regulatory review period occurred;
        (B) in the case of a patent which claims a method of
      manufacturing the product which primarily uses recombinant DNA
      technology in the manufacture of the product, the permission for
      the commercial marketing or use of the product after such
      regulatory review period is the first permitted commercial
      marketing or use of a product manufactured under the process
      claimed in the patent; or
        (C) for purposes of subparagraph (A), in the case of a patent
      which - 
          (i) claims a new animal drug or a veterinary biological
        product which (I) is not covered by the claims in any other
        patent which has been extended, and (II) has received
        permission for the commercial marketing or use in non-food-
        producing animals and in food-producing animals, and
          (ii) was not extended on the basis of the regulatory review
        period for use in non-food-producing animals,

      the permission for the commercial marketing or use of the drug or
      product after the regulatory review period for use in food-
      producing animals is the first permitted commercial marketing or
      use of the drug or product for administration to a food-producing
      animal.

    The product referred to in paragraphs (4) and (5) is hereinafter in
    this section referred to as the "approved product".
      (b) Except as provided in subsection (d)(5)(F), the rights
    derived from any patent the term of which is extended under this
    section shall during the period during which the term of the patent
    is extended - 
        (1) in the case of a patent which claims a product, be limited
      to any use approved for the product - 
          (A) before the expiration of the term of the patent - 
            (i) under the provision of law under which the applicable
          regulatory review occurred, or
            (ii) under the provision of law under which any regulatory
          review described in paragraph (1), (4), or (5) of subsection
          (g) occurred, and

          (B) on or after the expiration of the regulatory review
        period upon which the extension of the patent was based;

        (2) in the case of a patent which claims a method of using a
      product, be limited to any use claimed by the patent and approved
      for the product - 
          (A) before the expiration of the term of the patent - 
            (i) under any provision of law under which an applicable
          regulatory review occurred, and
            (ii) under the provision of law under which any regulatory
          review described in paragraph (1), (4), or (5) of subsection
          (g) occurred, and

          (B) on or after the expiration of the regulatory review
        period upon which the extension of the patent was based; and

        (3) in the case of a patent which claims a method of
      manufacturing a product, be limited to the method of
      manufacturing as used to make - 
          (A) the approved product, or
          (B) the product if it has been subject to a regulatory review
        period described in paragraph (1), (4), or (5) of subsection
        (g).

    As used in this subsection, the term "product" includes an approved
    product.
      (c) The term of a patent eligible for extension under subsection
    (a) shall be extended by the time equal to the regulatory review
    period for the approved product which period occurs after the date
    the patent is issued, except that - 
        (1) each period of the regulatory review period shall be
      reduced by any period determined under subsection (d)(2)(B)
      during which the applicant for the patent extension did not act
      with due diligence during such period of the regulatory review
      period;
        (2) after any reduction required by paragraph (1), the period
      of extension shall include only one-half of the time remaining in
      the periods described in paragraphs (1)(B)(i), (2)(B)(i),
      (3)(B)(i), (4)(B)(i), and (5)(B)(i) of subsection (g);
        (3) if the period remaining in the term of a patent after the
      date of the approval of the approved product under the provision
      of law under which such regulatory review occurred when added to
      the regulatory review period as revised under paragraphs (1) and
      (2) exceeds fourteen years, the period of extension shall be
      reduced so that the total of both such periods does not exceed
      fourteen years; and
        (4) in no event shall more than one patent be extended under
      subsection (e)(1) for the same regulatory review period for any
      product.

      (d)(1) To obtain an extension of the term of a patent under this
    section, the owner of record of the patent or its agent shall
    submit an application to the Director. Except as provided in
    paragraph (5), such an application may only be submitted within the
    sixty-day period beginning on the date the product received
    permission under the provision of law under which the applicable
    regulatory review period occurred for commercial marketing or use.
    The application shall contain - 
        (A) the identity of the approved product and the Federal
      statute under which regulatory review occurred;
        (B) the identity of the patent for which an extension is being
      sought and the identity of each claim of such patent which claims
      the approved product or a method of using or manufacturing the
      approved product;
        (C) information to enable the Director to determine under
      subsections (a) and (b) the eligibility of a patent for extension
      and the rights that will be derived from the extension and
      information to enable the Director and the Secretary of Health
      and Human Services or the Secretary of Agriculture to determine
      the period of the extension under subsection (g);
        (D) a brief description of the activities undertaken by the
      applicant during the applicable regulatory review period with
      respect to the approved product and the significant dates
      applicable to such activities; and
        (E) such patent or other information as the Director may
      require.

    For purposes of determining the date on which a product receives
    permission under the second sentence of this paragraph, if such
    permission is transmitted after 4:30 P.M., Eastern Time, on a
    business day, or is transmitted on a day that is not a business
    day, the product shall be deemed to receive such permission on the
    next business day. For purposes of the preceding sentence, the term
    "business day" means any Monday, Tuesday, Wednesday, Thursday, or
    Friday, excluding any legal holiday under section 6103 of title 5.
      (2)(A) Within 60 days of the submittal of an application for
    extension of the term of a patent under paragraph (1), the Director
    shall notify - 
        (i) the Secretary of Agriculture if the patent claims a drug
      product or a method of using or manufacturing a drug product and
      the drug product is subject to the Virus-Serum-Toxin Act, and
        (ii) the Secretary of Health and Human Services if the patent
      claims any other drug product, a medical device, or a food
      additive or color additive or a method of using or manufacturing
      such a product, device, or additive and if the product, device,
      and additive are subject to the Federal Food, Drug, and Cosmetic
      Act,

    of the extension application and shall submit to the Secretary who
    is so notified a copy of the application. Not later than 30 days
    after the receipt of an application from the Director, the
    Secretary receiving the application shall review the dates
    contained in the application pursuant to paragraph (1)(C) and
    determine the applicable regulatory review period, shall notify the
    Director of the determination, and shall publish in the Federal
    Register a notice of such determination.
      (B)(i) If a petition is submitted to the Secretary making the
    determination under subparagraph (A), not later than 180 days after
    the publication of the determination under subparagraph (A), upon
    which it may reasonably be determined that the applicant did not
    act with due diligence during the applicable regulatory review
    period, the Secretary making the determination shall, in accordance
    with regulations promulgated by such Secretary, determine if the
    applicant acted with due diligence during the applicable regulatory
    review period. The Secretary making the determination shall make
    such determination not later than 90 days after the receipt of such
    a petition. For a drug product, device, or additive subject to the
    Federal Food, Drug, and Cosmetic Act or the Public Health Service
    Act, the Secretary may not delegate the authority to make the
    determination prescribed by this clause to an office below the
    Office of the Director (!1) of Food and Drugs. For a product
    subject to the Virus-Serum-Toxin Act, the Secretary of Agriculture
    may not delegate the authority to make the determination prescribed
    by this clause to an office below the Office of the Assistant
    Secretary for Marketing and Inspection Services.

      (ii) The Secretary making a determination under clause (i) shall
    notify the Director of the determination and shall publish in the
    Federal Register a notice of such determination together with the
    factual and legal basis for such determination. Any interested
    person may request, within the 60-day period beginning on the
    publication of a determination, the Secretary making the
    determination to hold an informal hearing on the determination. If
    such a request is made within such period, such Secretary shall
    hold such hearing not later than 30 days after the date of the
    request, or at the request of the person making the request, not
    later than 60 days after such date. The Secretary who is holding
    the hearing shall provide notice of the hearing to the owner of the
    patent involved and to any interested person and provide the owner
    and any interested person an opportunity to participate in the
    hearing. Within 30 days after the completion of the hearing, such
    Secretary shall affirm or revise the determination which was the
    subject of the hearing and shall notify the Director of any
    revision of the determination and shall publish any such revision
    in the Federal Register.
      (3) For the purposes of paragraph (2)(B), the term "due
    diligence" means that degree of attention, continuous directed
    effort, and timeliness as may reasonably be expected from, and are
    ordinarily exercised by, a person during a regulatory review
    period.
      (4) An application for the extension of the term of a patent is
    subject to the disclosure requirements prescribed by the Director.
      (5)(A) If the owner of record of the patent or its agent
    reasonably expects that the applicable regulatory review period
    described in paragraph (1)(B)(ii), (2)(B)(ii), (3)(B)(ii),
    (4)(B)(ii), or (5)(B)(ii) of subsection (g) that began for a
    product that is the subject of such patent may extend beyond the
    expiration of the patent term in effect, the owner or its agent may
    submit an application to the Director for an interim extension
    during the period beginning 6 months, and ending 15 days, before
    such term is due to expire. The application shall contain - 
        (i) the identity of the product subject to regulatory review
      and the Federal statute under which such review is occurring;
        (ii) the identity of the patent for which interim extension is
      being sought and the identity of each claim of such patent which
      claims the product under regulatory review or a method of using
      or manufacturing the product;
        (iii) information to enable the Director to determine under
      subsection (a)(1), (2), and (3) the eligibility of a patent for
      extension;
        (iv) a brief description of the activities undertaken by the
      applicant during the applicable regulatory review period to date
      with respect to the product under review and the significant
      dates applicable to such activities; and
        (v) such patent or other information as the Director may
      require.

      (B) If the Director determines that, except for permission to
    market or use the product commercially, the patent would be
    eligible for an extension of the patent term under this section,
    the Director shall publish in the Federal Register a notice of such
    determination, including the identity of the product under
    regulatory review, and shall issue to the applicant a certificate
    of interim extension for a period of not more than 1 year.
      (C) The owner of record of a patent, or its agent, for which an
    interim extension has been granted under subparagraph (B), may
    apply for not more than 4 subsequent interim extensions under this
    paragraph, except that, in the case of a patent subject to
    subsection (g)(6)(C), the owner of record of the patent, or its
    agent, may apply for only 1 subsequent interim extension under this
    paragraph. Each such subsequent application shall be made during
    the period beginning 60 days before, and ending 30 days before, the
    expiration of the preceding interim extension.
      (D) Each certificate of interim extension under this paragraph
    shall be recorded in the official file of the patent and shall be
    considered part of the original patent.
      (E) Any interim extension granted under this paragraph shall
    terminate at the end of the 60-day period beginning on the date on
    which the product involved receives permission for commercial
    marketing or use, except that, if within that 60-day period the
    applicant notifies the Director of such permission and submits any
    additional information under paragraph (1) of this subsection not
    previously contained in the application for interim extension, the
    patent shall be further extended, in accordance with the provisions
    of this section - 
        (i) for not to exceed 5 years from the date of expiration of
      the original patent term; or
        (ii) if the patent is subject to subsection (g)(6)(C), from the
      date on which the product involved receives approval for
      commercial marketing or use.

      (F) The rights derived from any patent the term of which is
    extended under this paragraph shall, during the period of interim
    extension - 
        (i) in the case of a patent which claims a product, be limited
      to any use then under regulatory review;
        (ii) in the case of a patent which claims a method of using a
      product, be limited to any use claimed by the patent then under
      regulatory review; and
        (iii) in the case of a patent which claims a method of
      manufacturing a product, be limited to the method of
      manufacturing as used to make the product then under regulatory
      review.

      (e)(1) A determination that a patent is eligible for extension
    may be made by the Director solely on the basis of the
    representations contained in the application for the extension. If
    the Director determines that a patent is eligible for extension
    under subsection (a) and that the requirements of paragraphs (1)
    through (4) of subsection (d) have been complied with, the Director
    shall issue to the applicant for the extension of the term of the
    patent a certificate of extension, under seal, for the period
    prescribed by subsection (c). Such certificate shall be recorded in
    the official file of the patent and shall be considered as part of
    the original patent.
      (2) If the term of a patent for which an application has been
    submitted under subsection (d)(1) would expire before a certificate
    of extension is issued or denied under paragraph (1) respecting the
    application, the Director shall extend, until such determination is
    made, the term of the patent for periods of up to one year if he
    determines that the patent is eligible for extension.
      (f) For purposes of this section:
        (1) The term "product" means:
          (A) A drug product.
          (B) Any medical device, food additive, or color additive
        subject to regulation under the Federal Food, Drug, and
        Cosmetic Act.

        (2) The term "drug product" means the active ingredient of - 
          (A) a new drug, antibiotic drug, or human biological product
        (as those terms are used in the Federal Food, Drug, and
        Cosmetic Act and the Public Health Service Act), or
          (B) a new animal drug or veterinary biological product (as
        those terms are used in the Federal Food, Drug, and Cosmetic
        Act and the Virus-Serum-Toxin Act) which is not primarily
        manufactured using recombinant DNA, recombinant RNA, hybridoma
        technology, or other processes involving site specific genetic
        manipulation techniques,

      including any salt or ester of the active ingredient, as a single
      entity or in combination with another active ingredient.
        (3) The term "major health or environmental effects test" means
      a test which is reasonably related to the evaluation of the
      health or environmental effects of a product, which requires at
      least six months to conduct, and the data from which is submitted
      to receive permission for commercial marketing or use. Periods of
      analysis or evaluation of test results are not to be included in
      determining if the conduct of a test required at least six
      months.
        (4)(A) Any reference to section 351 is a reference to section
      351 of the Public Health Service Act.
        (B) Any reference to section 503, 505, 512, or 515 is a
      reference to section 503, 505, 512, or 515 of the Federal Food,
      Drug, and Cosmetic Act.
        (C) Any reference to the Virus-Serum-Toxin Act is a reference
      to the Act of March 4, 1913 (21 U.S.C. 151-158).
        (5) The term "informal hearing" has the meaning prescribed for
      such term by section 201(y) (!2) of the Federal Food, Drug, and
      Cosmetic Act.

        (6) The term "patent" means a patent issued by the United
      States Patent and Trademark Office.
        (7) The term "date of enactment" as used in this section means
      September 24, 1984, for a human drug product, a medical device,
      food additive, or color additive.
        (8) The term "date of enactment" as used in this section means
      the date of enactment of the Generic Animal Drug and Patent Term
      Restoration Act for an animal drug or a veterinary biological
      product.

      (g) For purposes of this section, the term "regulatory review
    period" has the following meanings:
        (1)(A) In the case of a product which is a new drug, antibiotic
      drug, or human biological product, the term means the period
      described in subparagraph (B) to which the limitation described
      in paragraph (6) applies.
        (B) The regulatory review period for a new drug, antibiotic
      drug, or human biological product is the sum of - 
          (i) the period beginning on the date an exemption under
        subsection (i) of section 505 or subsection (d) of section 507
        (!2) became effective for the approved product and ending on
        the date an application was initially submitted for such drug
        product under section 351, 505, or 507,(!2) and
          (ii) the period beginning on the date the application was
        initially submitted for the approved product under section 351,
        subsection (b) of section 505, or section 507 (!2) and ending
        on the date such application was approved under such section.

        (2)(A) In the case of a product which is a food additive or
      color additive, the term means the period described in
      subparagraph (B) to which the limitation described in paragraph
      (6) applies.
        (B) The regulatory review period for a food or color additive
      is the sum of - 
          (i) the period beginning on the date a major health or
        environmental effects test on the additive was initiated and
        ending on the date a petition was initially submitted with
        respect to the product under the Federal Food, Drug, and
        Cosmetic Act requesting the issuance of a regulation for use of
        the product, and
          (ii) the period beginning on the date a petition was
        initially submitted with respect to the product under the
        Federal Food, Drug, and Cosmetic Act requesting the issuance of
        a regulation for use of the product, and ending on the date
        such regulation became effective or, if objections were filed
        to such regulation, ending on the date such objections were
        resolved and commercial marketing was permitted or, if
        commercial marketing was permitted and later revoked pending
        further proceedings as a result of such objections, ending on
        the date such proceedings were finally resolved and commercial
        marketing was permitted.

        (3)(A) In the case of a product which is a medical device, the
      term means the period described in subparagraph (B) to which the
      limitation described in paragraph (6) applies.
        (B) The regulatory review period for a medical device is the
      sum of - 
          (i) the period beginning on the date a clinical investigation
        on humans involving the device was begun and ending on the date
        an application was initially submitted with respect to the
        device under section 515, and
          (ii) the period beginning on the date an application was
        initially submitted with respect to the device under section
        515 and ending on the date such application was approved under
        such Act or the period beginning on the date a notice of
        completion of a product development protocol was initially
        submitted under section 515(f)(5) and ending on the date the
        protocol was declared completed under section 515(f)(6).

        (4)(A) In the case of a product which is a new animal drug, the
      term means the period described in subparagraph (B) to which the
      limitation described in paragraph (6) applies.
        (B) The regulatory review period for a new animal drug product
      is the sum of - 
          (i) the period beginning on the earlier of the date a major
        health or environmental effects test on the drug was initiated
        or the date an exemption under subsection (j) of section 512
        became effective for the approved new animal drug product and
        ending on the date an application was initially submitted for
        such animal drug product under section 512, and
          (ii) the period beginning on the date the application was
        initially submitted for the approved animal drug product under
        subsection (b) of section 512 and ending on the date such
        application was approved under such section.

        (5)(A) In the case of a product which is a veterinary
      biological product, the term means the period described in
      subparagraph (B) to which the limitation described in paragraph
      (6) applies.
        (B) The regulatory period for a veterinary biological product
      is the sum of - 
          (i) the period beginning on the date the authority to prepare
        an experimental biological product under the Virus-Serum-Toxin
        Act became effective and ending on the date an application for
        a license was submitted under the Virus-Serum-Toxin Act, and
          (ii) the period beginning on the date an application for a
        license was initially submitted for approval under the Virus-
        Serum-Toxin Act and ending on the date such license was
        issued.

        (6) A period determined under any of the preceding paragraphs
      is subject to the following limitations:
          (A) If the patent involved was issued after the date of the
        enactment of this section, the period of extension determined
        on the basis of the regulatory review period determined under
        any such paragraph may not exceed five years.
          (B) If the patent involved was issued before the date of the
        enactment of this section and - 
            (i) no request for an exemption described in paragraph
          (1)(B) or (4)(B) was submitted and no request for the
          authority described in paragraph (5)(B) was submitted,
            (ii) no major health or environmental effects test
          described in paragraph (2)(B) or (4)(B) was initiated and no
          petition for a regulation or application for registration
          described in such paragraph was submitted, or
            (iii) no clinical investigation described in paragraph (3)
          was begun or product development protocol described in such
          paragraph was submitted,

        before such date for the approved product the period of
        extension determined on the basis of the regulatory review
        period determined under any such paragraph may not exceed five
        years.
          (C) If the patent involved was issued before the date of the
        enactment of this section and if an action described in
        subparagraph (B) was taken before the date of the enactment of
        this section with respect to the approved product and the
        commercial marketing or use of the product has not been
        approved before such date, the period of extension determined
        on the basis of the regulatory review period determined under
        such paragraph may not exceed two years or in the case of an
        approved product which is a new animal drug or veterinary
        biological product (as those terms are used in the Federal
        Food, Drug, and Cosmetic Act or the Virus-Serum-Toxin Act),
        three years.

      (h) The Director may establish such fees as the Director
    determines appropriate to cover the costs to the Office of
    receiving and acting upon applications under this section.