How to Calculate Patent Terms

Before 1995, an unadjusted U.S. patent term was 17 years after the date of issue. After 1995, patent law of the United States was changed to be in conformity with the WTO’s Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPs). Patent term calculation became much more complex.

There are two rules for patent term calculation:

Before URAA After URAA

Issued date < June 8, 1978 Filing date < June 8, 1995 and

Issued date ≥ June 8, 1978 Filing date ≥ June 8, 1995

Rule 1 Rule 1 or 2, whichever is longer Rule 2

CHART 6.2 UNADJUSTED PATENT TERM CALCULATION

The statutory text for the determination of patent terms reads:

35 U.S.C. § 154 (a)(2): Subject to the payment of fees under this title, such grant shall be for a term beginning on the date on which the patent issues and ending 20 years from the date on which the application for the patent was filed in the United States or, if the application contains a specific reference to an earlier filed application or applications under section 120, 121, or 365(c) of this title, from the date on which the earliest such application was filed.

35 U.S.C. § 154 (c)(1): The term of a patent that is in force on or that results from an application filed before the date that is 6 months after the date of the enactment of the Uruguay Round Agreements Act³¹⁷ shall be the greater of the 20-year term as provided in subsection (a), or 17 years from grant, subject to any terminal disclaimers.

317 June 8, 1995.

Because patent term is now defined by the application’s filing date, rather than the issue date, the new term amendment has reduced the incentive for ill-willed patentees to file so-called “submarine patents.” The amendment also makes prolonged patent prosecution less lucrative. The early publication of patent applications now generally occurs 18 months after filing.

Many pre-June 8, 1995 patents enjoyed an unexpected term extension because of this amendment. For example, U.S. Patent No. 4,174,100, enforced by a General Exclusion Order, was expected to expire on November 13, 1996 at the time of the decision, had its term extended to March 27, 1998.³¹⁸ As a result, the remaining life of said patent gained a 12 per cent extension (4665 days versus 4165 days) after the amendment unexpected at the time of issue.

6.2.2.1 Patent Term Extension

Other than the batch term extension enacted by the URAA, patent terms may be subject to extensions based on other laws as well, e.g., the “patent term adjustment rule” of the American Inventors Protection Act (AIPA) (November 29, 1999). To the best of the author’s knowledge, no patent ever litigated at the USITC was subjected to such an extension.

6.2.2.2 Patent Term Reduction

A terminal disclaimer can be used as a work around to prevent non-statutory type double patenting by the same patentee.³¹⁹ Therefore, the presence of a terminal disclaimer usually implies the existence of an earlier patent by the same patentee or assignee which may or may not be included in the same Section 337 investigation. Since the patentee already had a patent covering the scope of the new patent application, the later application can only be approved if the patentee disclaimed the part of its term subsequent to the former patent’s expiration date.

Nearly all disclaimer-carrying and USITC-litigated patents belong to the above type.

Patentees who litigate actively may be more likely to file applications covering essentially the same scope in order to minimize the risk of leaving something unclaimed just because of improperly drafted claims.

318 Woodworking Machines, Commission Action and Order, Inv. No. 337-TA-174 (1985).

319 MPEP § 804.02, http://www.uspto.gov/web/offices/pac/mpep/documents/0800_804_02.htm .

CHART 6.3 PATENT TERM CALCULATION (W/ TERMINAL DISCAIMER)

In the above case, a patent’s term is decided by the term of another patent that belongs to the same patentee. It is noteworthy that the terminal disclaimer printed on a pre-URAA patent was still eligible to the URAA term adjustment if its referenced patent’s term was extended by the law:³²⁰

To determine the “original expiration date” of a patent subject to a terminal disclaimer, it is generally necessary to examine the language of the terminal disclaimer in the patent file history. If the disclaimer disclaims the terminal portion of the term of the patent which would extend beyond the expiration date of an earlier issued patent, then the expiration date of the earlier issued patent determines the expiration date of the patent subject to the terminal disclaimer. Before June 8, 1995, the terminal disclaimer date was printed on the face of the patent; the date was determined from the expected expiration date of the earlier issued patent based on a seventeen year term measured from grant. When 35 U.S.C. 154 was amended such that all patents (other than design patents) that were in force on June 8, 1995, or that issued on an application that was filed before June 8, 1995, have a term that is the greater of the “twenty year term” or seventeen years from the patent grant, the terminal disclaimer date as printed on many patents became incorrect. If the terminal disclaimer of record in the patent file disclaims the terminal portion of the patent subsequent to the full statutory term of a referenced patent (without identifying a specific date), then the date printed on the face of the patent is incorrect when the full statutory term of the referenced patent is changed as a result of 35 U.S.C. 154(c). That is, the referenced patent’s “twenty year term”

is longer than the seventeen year term. In such a case, a patentee may request a Certificate of Correction under 37 CFR 1.323 to correct the information printed on the face of the patent. However, if the terminal disclaimer of record in the patent file disclaims the terminal portion of the patent subsequent to a specific date, without reference to the full statutory term of a referenced patent, then the expiration date is the date specified. Several decisions related to disclaimers are posted in the Freedom of Information Act (FOIA) section of the USPTO Internet site (www.uspto.gov).

320 Expiration Date of Patents with Terminal Disclaimers, available at http://www.uspto.gov/web/offices/pac/mpep/documents/2700_2701.htm .

The above scenario has been discussed and answered at the time of URAA’s issuance.³²¹

Many USITC-litigated patents that carried terminal disclaimers did enjoy above-mentioned term extensions.

A terminal disclaimer does not restrict the extended term that has been granted under 35 U.S.C. §156. (King Pharma v. Teva, 78 USPQ2d 1237 (D.N.J. 2006)). This rule is also not applicable to any USITC-litigated patent.

6.2.2.3 Patent Disclaim

A terminal disclaimer disclaims a part of a patent’s term in the future. In some other cases, a patentee may also explicitly disclaim the patent’s immediate remaining term by adding a disclaimer at the last page of the patent. Some patents involved in past Section 337 investigations have been released to the public domain this way.

For example, U.S. Patent No, 3,444,704,³²² owned by Marvel Specialty Co., Inc. of North Carolina, was disclaimed by its assignee right after the ALJ found Respondents not in violation.

• May 20, 1969: issued.

• January 25, 1977: disclaimed date.

• March 30, 1977: termination of investigation.

• May 20, 1986: expected expiration date.

Other than adding a disclaimer as a statement, patents involved in a lost case may not be renewed. On the contrary, if the ALJ finds violation, it would be quite reasonable to expect the patentee to pay for the patent’s renewal at least for a period of time long enough to generate profit.

A U.S. patent remains valid upon the timely payment of maintenance fees within its predetermined term. Many unprofitable or defeated patents were abandoned by their owners only a few years after issue. The author assumes at the time of investigation, the ALJ would

321 E.g., Lois Boland, GATT/TRIPS: a Response from the United States Patent and Trademark Office, 22 AIPLA Q.J. 425, 445 (1994); PATENT AND TRADEMARK OFFICE, QUESTIONS AND ANSWERS REGARDING THE GATT URUGUAY ROUND NAFTACHANGES TO U.S.PATENT LAW AND PRACTICE (1995).

322 Knitting Machines and Throat Plates, Inv. No. 337-TA-28.

take the full remaining life of a patent into consideration when deciding the type and scope of exclusion orders. If the patent was relatively young, with many years of effective remaining life, the ALJ could be somewhat reluctant to issue a broad General Exclusion Order. On the other hand, if Complainant has only one aged patent that is being violated; the ALJ may be more likely to grant a broad General Exclusion Order.

6.2.2.4 The URAA’s Enactment Date

The URAA was enacted on January 25, 1995 and went into enforcement on June 8, 1995. January 25, 1995 was the earliest date when the ALJ was supposed to know about the coming rule change regarding patent term calculation.

Before the enactment of the URAA, there had been various patent term rules proposed by Congress members. The ALJs probably could not predict which proposal would be selected in 1993 or 1994. Therefore, the author assumes the ALJs learned about the final patent term rule at the URAA’s enactment date.

The legislation process of the URAA lasted for about two years. The first patent law amendment was proposed as early as January 1993. It was more than one year before the conclusion of the Uruguay Round by the signing of Marrakesh Agreement on April 15, 2004.

The legislation process ends on December 8, 1994. It is safe to assume after December 8, 1994, all ALJs learned the details about the coming rule change.

Title Short title Sponsor Latest Major Action Status 103rd U.S. Congress

1/21/1993 S. 149

A bill to amend section 182 of the Trade Act of

Read twice and referred to the Committee on

4/21/1994

A bill to implement the intellectual property right of patents, and for other purposes.

Sen Robert J.

Dole (R-KS) 1/26/1995 Referred to Senate subcommittee.

Read twice and referred to the Committee on Judiciary.

CHART 6.4 URAA LEGISLATIVE HISTORY³²³