AbbVie’s U.S. Humira revenue fell from $18,619 million in 2022 to $12,160 million in 2023. That is a drop of $6,459 million, or 34.7% [1][2]. The year-end 2022 number came six years after the U.S. composition-of-matter patent on adalimumab expired [9]. In the meantime, AbbVie had built one of the largest patent estates in pharmaceutical history. A reader could take that as proof that more patent filings buy more time. This article argues the opposite reading: the filings did not buy the time. Settlements did, and the filings supplied the leverage for those settlements.
The difference matters because patent teams still talk about continuations as if they were a way to lengthen a monopoly. They are not. A continuation application cannot outlast its family. Since 2023, the Federal Circuit has also narrowed the one term benefit that continuation families can collect. Since January 2025, the USPTO has charged more for late continuations. Defending the resulting patents in court still costs money per patent. This article lays out the rules, the dates, the numbers and the calculations. It separates documented facts from analysis throughout.
The Short Answer
Can a Continuation Patent Extend Drug Patent Term?
No. A patent that claims benefit to an earlier application expires 20 years from the filing date of the earliest such application [3]. A continuation filed in 2026 that claims benefit to a 2008 application would expire in 2028 under that rule, before any term adjustment (analysis based on the statutory rule). The continuation adds claims. It does not add years.
What Can a Continuation Still Do for a Brand Manufacturer?
A continuation can keep a family open so the owner can write new claims against a competitor’s actual product. It can also add to the count of patents a challenger must read, analyze and litigate. Those are real benefits. They are benefits of scope and leverage, not of time. The sections below test how much that leverage was worth in the best-known example, Humira, and how much it cost.
The Seven Findings That Matter
A continuation expires 20 years from the earliest filing date it claims, so it cannot outlast its family before patent term adjustment [3].
In re Cellect (Fed. Cir. 2023) counts patent term adjustment when a court measures obviousness-type double patenting. Allergan v. MSN (Fed. Cir. 2024) then ruled that a later-filed, later-issued continuation cannot invalidate the first-filed, first-issued patent in its own family [4][5].
The USPTO fee schedule that took effect on January 19, 2025 adds a $2,700 surcharge for continuations filed six or more years after the earliest benefit date and $4,000 at nine or more years (large entity) [7]. By calculation, the nine-year surcharge is 48% higher than the six-year surcharge.
I-MAK counted 247 patent applications on Humira and found that 89% were filed after the drug reached the market in 2002 [8]. By calculation, that is about 220 applications. U.S. biosimilar entry under the Amgen license began on January 31, 2023, about 73 months after the U.S. composition-of-matter patent expired in December 2016 [9][10].
Courts defined the patent counts for only two Humira disputes. One covered 10 of 61 identified patents and the other covered 8 of 74 [12]. By calculation, that is 16.4% and 10.8% of the identified patents.
Novartis won a written-description appeal on Entresto’s 2002 core patent, but the patent had already reached the end of its term. A later amorphous-form patent, listed as U.S. 11,096,918, was not in the Orange Book and lost on non-infringement in district court [13][15][16].
Patents based on continuation applications made up 52% of litigated patents in a 1976-2000 dataset, while continuations were filed in 23% of applications [17].
Methodology and Definitions
What Data Does This Article Use?
This article uses public documents only. The sources are the USPTO’s Manual of Patent Examining Procedure, Federal Circuit opinions and summaries of those opinions, the Congressional Research Service, AbbVie’s SEC filings and results releases, the USPTO fee notice as reported by a law firm, a 2018 I-MAK press release, and a 2003 academic working paper. DrugPatentWatch is the reference platform used to organize drug-patent records, and its published analysis is cited where it reports litigation counts. DrugPatentWatch is not used here as a substitute for the court and agency records.
How Were the Calculations Made?
Every figure labeled “by calculation” or “analysis” is derived from the cited inputs. Revenue changes use the dollar figures in AbbVie’s releases. The 73-month gap counts from the end of December 2016 to January 31, 2023, because the source gives the patent expiry only as “December 2016.” The 220-application figure multiplies 247 by 0.89 and rounds. Percentage shares divide the court-defined patent count by the identified patent count. No duplicates were removed because the inputs are single reported totals.
Key Definitions
Continuation Application
A continuation is a later application that claims benefit to an earlier application and uses the same disclosure. It can seek new claims. Its term is measured from the earliest claimed filing date [3].
Obviousness-Type Double Patenting (ODP)
ODP is a court-made doctrine that bars a second patent on an obvious variant of an earlier patent by the same inventor. Continuation patents often raise the issue because they share disclosure with a parent [6].
Terminal Disclaimer
A terminal disclaimer gives up part of a patent’s term. Applicants use one to overcome an ODP rejection. The disclaimed patent is enforceable only while it stays commonly owned with the earlier patent [6].
Patent Term Adjustment (PTA) and Patent Term Extension (PTE)
PTA compensates for USPTO delay and comes from 35 U.S.C. 154. PTE compensates for FDA review time and comes from 35 U.S.C. 156. The Federal Circuit treats the two differently for ODP purposes [4].
What Are the Limits of This Analysis?
The sources do not say which Humira patents carried the most weight in settlement talks. They do not give the Amgen settlement’s financial terms [10]. The AIPLA cost bands are reported through a secondary source and top out at $25 million at risk [12]. The Entresto sources end in mid-2025, and the sources reviewed here do not report the outcome of any appeal of the ‘918 ruling. Readers should treat the cost illustrations as scaling exercises and not as estimates of actual spending.
How Does the 20-Year Clock Work for Continuations?
What Is the Earliest-Filing-Date Rule?
The USPTO’s MPEP states the rule for applications filed on or after June 8, 1995. The term ends 20 years from the filing date in the United States. If the application contains a specific reference to an earlier filed application under sections 120, 121 or 365(c), the term runs 20 years from the filing date of the earliest such application [3]. The statute adds section 386(c) to that list [3].
Why Does a Late Continuation Have Little Life Left?
The clock starts at the first application, not at the continuation. Take a family first filed in January 2008. Its 20-year date is January 2028. A continuation filed in October 2026 in that family would have about 15 months of term left before any adjustment (analysis). A drug company cannot buy a fresh 20 years by filing again. It can only claim new subject matter in a new family, and that family then needs its own support in a specification.
Where Real Term Comes From
Term beyond the 20-year date comes from PTA for USPTO delay and PTE for FDA review. Regulatory exclusivities that the FDA grants add protection separately. Entresto shows two of these in one product. Its core patent, U.S. 8,101,659, has a January 17, 2002 priority date and expired on January 15, 2025 after PTE [13]. Pediatric exclusivity then extended its protection to July 15, 2025 [15]. None of that came from filing more continuations.
What Does Obviousness-Type Double Patenting Do to Continuation Families?
In re Cellect (Fed. Cir. 2023): Why Did Term Adjustment Become a Liability?
In re Cellect, No. 22-1293, was decided on August 28, 2023 by Judges Lourie, Dyk and Reyna [4]. The case involved five patents in one family that covered image sensors. All traced to the same original application. Without PTA, they would have expired together. Four had PTA and the last-filed one did not [4].
What the Court Held
The court affirmed the invalidation of the four PTA-bearing patents. It held that a patent with PTA is measured by its expiration date after PTA is added. A patent with PTE is measured before PTE is added [4].
Why the Court Treated PTA and PTE Differently
The court reasoned that PTA and PTE come from different statutes. Section 154 says PTA cannot extend a patent beyond a date set in a terminal disclaimer. The court read that as Congress acknowledging that ODP can apply to PTA. Section 156 has no similar reference. The court also held that good faith and lack of gamesmanship do not entitle an applicant to term it would not otherwise have [4].
Allergan v. MSN (Fed. Cir. 2024): What Is the First-Filed, First-Issued Rule?
Allergan USA, Inc. v. MSN Laboratories Private Ltd., No. 24-1061, was decided on August 13, 2024 and is precedential [5]. The ‘356 patent covers the compound eluxadoline. It received 1,107 days of PTA, which is about 3.03 years by calculation. Two continuation patents, the ‘011 and ‘709, share its priority date. Neither received PTA, so each expires earlier [5].
The Holding
The Federal Circuit reversed the district court. It held that a later-filed, later-issued patent cannot be an ODP reference against the first-filed, first-issued patent in its family. The court called that “the only conclusion consistent with the purpose of the ODP doctrine,” which is to prevent a second patent from effectively extending the life of a first patent [5].
What the Ruling Leaves Open
The court said Cellect “does not address, let alone resolve,” when a claim can serve as an ODP reference [5]. The update to the source also notes that rehearing or certiorari petitions remained possible [5]. The practical result is narrow. The first-filed, first-issued patent keeps its PTA. Continuations in later-issued positions remain exposed to ODP and often need terminal disclaimers.
What Do Terminal Disclaimers Cost the Owner?
A terminal disclaimer ties the child patent’s enforceability to common ownership with the parent and shortens its term to the parent’s [6]. That is the trade. The owner gets the allowance and gives up any term the child might otherwise have had. In a continuation family, the terminal disclaimer is the mechanism that turns a “new patent” into a patent with the old patent’s end date.
Did the USPTO Make Continuations More Expensive?
What Is the 2025 Continuing Application Surcharge?
Yes, for late filings. The USPTO final fee rule took effect on January 19, 2025. It adds a surcharge to continuing applications, divisionals included, based on how long after the earliest benefit date the application is filed [7].
Filing timing (large entity)
Surcharge
Source
Six or more years after earliest benefit date
$2,700
[7]
Nine or more years after earliest benefit date
$4,000
[7]
Difference between the two tiers (calculation)
$1,300, or 48% above the six-year tier
Analysis
What Are the RCE and IDS Fee Changes?
The same rule set the first request for continued examination at $1,500, up 10%. Second and later requests are $2,860, up 43% [7]. Information disclosure statements now carry size fees for large entities: $200 above 50 items, $500 above 100 items and $800 above 200 items, each less any amount previously paid [7]. Large families with heavy prior-art lists feel these fees first.
Is the Surcharge Large Compared with Litigation Cost?
No. The $4,000 top surcharge equals about 0.13% of a $3 million per-patent trial-and-appeal cost (calculation, using the figure in the cost section below). The filing fee is not where the bill sits. The bill sits in defending the issued patents.
What Happened to the Terminal Disclaimer Rule?
The USPTO proposed a rule on May 10, 2024. It would have made a disclaimed patent unenforceable if a court or the USPTO finally held any claim of the original patent unpatentable on novelty or non-obviousness grounds [6]. The Office had drawn more than 200 comments on its October 24, 2022 request for comments and nearly 350 on the proposed rule. Five former USPTO Directors or Deputy Directors urged withdrawal [6]. The USPTO withdrew the proposal on December 4, 2024, citing “resource constraints” [6]. As a result, continuation families with terminal disclaimers still face no validity-linkage rule from the agency.
Case Study: What Did Humira’s 247 Applications Deliver?
Humira Patent Timeline, 2016 to 2023
Date
Event
Source
2002
Humira approved and on the market, per I-MAK
[8]
December 2016
U.S. composition-of-matter patent on adalimumab expires
[9]
Early 2017
AbbVie states non-composition patents expire “no earlier than 2022”
[9]
September 28, 2017
AbbVie and Amgen settle; U.S. license start set for January 31, 2023; EU start October 16, 2018
[10]
December 18, 2018
I-MAK reports 247 applications, 89% filed after market entry
[8]
August 1, 2022
Seventh Circuit affirms dismissal of antitrust claims; opinion refers to 132 patents
[11]
January 31, 2023
U.S. license period begins for Amgen’s biosimilar
[10]
What Delivered the 2023 Date: Patents or Settlements?
The documents point to settlements. The Amgen settlement resolved all IP litigation over Amgen’s proposed biosimilar and gave Amgen a non-exclusive license. Neither company disclosed financial terms [10]. The U.S. license start came about 73 months after the compound patent expired (calculation, from [9] and [10]). The EU start came about 51 months earlier than the U.S. start (calculation: October 16, 2018 to January 31, 2023). The sources do not state why the dates differ.
Where the Patents Were Actually Tested
DrugPatentWatch’s litigation-budget analysis reports that AbbVie v. Amgen proceeded on 10 of the 61 patents identified in the biosimilar disclosure process before settling in September 2017. It reports that AbbVie v. Boehringer Ingelheim proceeded on 8 patents, from 74 that AbbVie identified as infringed [12]. By calculation, those court-defined counts are 16.4% and 10.8% of the identified patents. The article says the other six biosimilar disputes settled without a court-defined count [12].
What This Means for the Leverage Argument
A large estate forces a challenger to price in the risk of many patents. It does not require the owner to win on many. In both litigated disputes, most of the identified patents never went to a court-defined contest. The leverage worked as a negotiating position. It did not work as a record of adjudicated wins.
Was the Humira Patent Thicket Lawful? The Seventh Circuit Said Yes
On August 1, 2022, the Seventh Circuit, in an opinion by Judge Easterbrook, agreed with the district court that AbbVie’s settlements and its Humira portfolio did not violate the Sherman Act. It affirmed dismissal of a complaint brought by welfare-benefit plans that pay for Humira. The coverage records 132 patents in the portfolio at issue [11]. The court found the U.S. settlement was not a reverse-payment settlement, even when read with the European settlements [11].
The opinion asked: “what’s wrong with having lots of patents?” [11]. It also noted that “Thomas Edison alone held 1,093 U.S. patents” [11]. The ruling matters for brand owners because it means a thicket, standing alone, was not an antitrust problem on those facts. It does not mean the thicket extended the legal term of any patent.
What Does the Revenue Data Show?
Metric
2022
2023
Change
Source
U.S. Humira net revenue
$18,619 million
$12,160 million
-$6,459 million (-34.7%)
[1][2]
Global Humira net revenue
$21,237 million
$14,404 million
-$6,833 million (-32.2%)
[1][2]
The dollar differences are calculations. The percentage changes match the reported figures in AbbVie’s releases [1][2]. The data show two facts. U.S. revenue stayed above $18 billion in the sixth year after the compound patent expired. It also dropped by about a third in the first year of biosimilar entry. Both facts fit a story in which the settlement date, not the patent expiry date, controlled the revenue cliff.
Case Study: What Happened to Entresto’s Secondary Patents?
The 2002 Core Patent: A Written-Description Win That Arrived Late
Novartis Pharmaceuticals Corp. v. Torrent Pharma Inc., Nos. 2023-2218, -2220 and -2221, was decided on January 10, 2025 by Judges Lourie, Prost and Reyna [13]. The only patent at issue was U.S. 8,101,659, with a January 17, 2002 priority date and a January 15, 2025 expiry after PTE [13]. The district court had held claims 1 to 4 invalid for lack of written description, because complexes of valsartan and sacubitril were unknown in 2002 [13].
What the Federal Circuit Changed
The Federal Circuit reversed on written description. It said the claims cover a physical combination of valsartan and sacubitril, which the specification adequately describes. It affirmed that the patent was enabled and not obvious [13]. It wrote that “[t]he invention is, for purposes of the ‘written description’ inquiry, whatever is now claimed” [13].
Why This Case Matters for Continuation Drafting
The dispute shows how claim language written to cover later-discovered embodiments gets tested against the original specification. Novartis kept its patent on appeal. But the district court’s invalidity ruling had stood until the Federal Circuit reversed it in January 2025, five days before the patent’s PTE expiry date [13]. The case does not involve a continuation. I use it here only to show how long a written-description fight can run against a patent’s clock.
The ‘918 Patent: Not Listed, and It Lost on Infringement
U.S. 11,096,918 is directed to an amorphous solid form and is due to expire in November 2026 [15]. In August 2024, the District of Delaware denied Novartis a preliminary injunction against MSN’s generic, which FDA had approved on July 24, 2024. Judge Andrews said Novartis had not shown it was very likely to win on infringement [14]. In April 2025, the court ordered FDA to reset MSN’s approval date to no earlier than July 16, 2025. Novartis and MSN then settled the ‘659 portion of the dispute in June 2025 [15].
The district court later ruled for MSN on non-infringement of the ‘918 patent. It found Novartis’s expert analysis unreliable and drew an adverse inference because Novartis did not produce the glassy solid sample [16]. A law-firm summary says the ‘918 patent was not listed in the Orange Book, so MSN faced no barrier to launch on FDA approval [16]. The summary reports that Novartis was expected to appeal. The sources reviewed for this article do not report the appeal’s outcome. I could not confirm whether the ‘918 patent claims benefit to an earlier application.
What the Sequence Shows
The later patent had a later expiry date than the core patent. It still did not stop the generic. A later expiry date and an enforceable claim are different things. The claim has to read on the accused product, and the patent has to carry the procedural weight of listing if the owner wants an automatic stay.
What Does It Cost to Defend Each Extra Patent?
What Are the AIPLA Cost Bands per Patent?
DrugPatentWatch reports that Ramey LLP, citing the AIPLA 2023 Report of the Economic Survey, gives per-patent, per-side costs by amount at risk. The article could not verify the figures against the AIPLA report itself, and this article repeats that caveat [12].
Amount at risk
Through discovery and claim construction
Through trial and appeal
Source
Under $1 million
$300,000 median
$600,000
[12]
$1 million to $10 million
About $600,000
About $1 million
[12]
$10 million to $25 million
About $1.5 million
About $3 million
[12]
What Would Humira-Scale Disputes Cost on These Bands?
This is an illustration, not an estimate. The top band tops out at $25 million at risk, and Humira’s U.S. revenue was $18.6 billion in 2022 [1]. Costs at that scale are likely higher, but the source does not say by how much. If the top band’s roughly $3 million per patent applied, 10 patents would cost about $30 million per side through trial and appeal, and 8 patents about $24 million (calculation). Those totals count only the patents that reached a court-defined dispute [12].
Who Pays for the Rest of the Estate?
The patents that never reached a court-defined count still cost money to prosecute, maintain, review and assert in claim charts. The sources reviewed here do not quantify that cost. A fair reading is that the bill grows with the count of patents even when the dispute list stays small.
Why Are Continuation Patents Litigated So Often?
What Do the 23% and 52% Figures Say?
“continuations are filed in 23% of all patent applications,” but “patents based on continuation applications represent 52% of all litigated patents.” (Lemley & Moore, 2003) [17]
The authors built a dataset of 2,224,379 U.S. patents issued from 1976 through 2000. They argued that continuations serve little useful purpose and that existing controls were insufficient [17]. The working paper was published as Lemley and Moore’s “Ending Abuse of Patent Continuations” in the Boston University Law Review in 2004.
What Do the Figures Not Show?
The data end in 2000. They cover all technologies, not drugs. A patent based on a continuation may be litigated more often because it was drafted against a known product, because it is a later patent in a valuable family, or because the family is large. The figures show an association. They do not show cause. They also pre-date Cellect, Allergan and the 2025 fee schedule.
A Framework: What Can a Continuation Buy?
This is an original framework, not an industry classification. It sorts what an owner can get from continuation filings into four functions and tests each against the evidence in this article.
Function
What it does
Limit
Evidence
Scope
New claims aimed at a competitor’s product
Needs written-description support; claims read against the original specification
[13]
Leverage
More patents for a challenger to assess
Courts defined counts for 10 of 61 and 8 of 74 identified patents
[12]
Hedge
Backup claims if parent claims fall
Child patents often need terminal disclaimers and share the parent’s end date
[3][6]
Time
More years of exclusivity
Not available; term runs from the earliest filing, and ODP targets PTA
[3][4][5]
Scope: Claims Drafted Against a Real Product
Scope is the strongest use. An owner can watch a competitor’s filing and draft claims that read on it. The Novartis case shows the limit. The claims are read against the original specification, and a challenger can argue the original document did not describe what the new claims cover [13].
Leverage: The Humira Pattern
Leverage worked at Humira. A settlement date of January 31, 2023 followed a thicket of 247 applications and 132 patents in the Seventh Circuit’s count [8][10][11]. The leverage came with a cost, and the cost grows when the law moves against the owner.
Hedge: Backup Claims in a Pending Family
Keeping a continuation pending lets an owner pursue alternative claims if the first set fails. That is a sound reason to file. It is also a reason to expect a terminal disclaimer, which ties the hedge to the parent’s end date [6].
Time: The Function Continuations Cannot Perform
Time comes from PTE, regulatory exclusivities and new families with their own filing dates. A continuation can carry PTA, but Cellect makes that PTA count in the ODP comparison, and Allergan protects it only for the first-filed, first-issued patent [4][5].
What This Means for Brand Manufacturers
Where Should a Brand Team Put Its Patent Budget?
This section is analysis. A brand team should rank spending by function. Money spent on a continuation that adds scope against a known competitor product has a clear return. Money spent on a continuation to add count has a weaker return as ODP and fee rules tighten. Money spent on new-family filings for genuinely new inventions, such as a new form with its own written-description support, buys real term. The Entresto ‘918 patent shows that a new-form patent can carry a later expiry date, but it also shows that infringement and Orange Book listing still decide whether the date matters [15][16].
How Should Teams Plan the Family Calendar?
Teams should record the earliest claimed filing date for every family member and the PTA each carries. They should flag children with terminal disclaimers. They should track the surcharge dates: six years and nine years after the earliest benefit date [7]. A late continuation costs more, so it should have a specific competitor target.
What This Means for Generic and Biosimilar Developers
How Should a Challenger Read a Large Estate?
A challenger should sort the estate by family before sorting by count. Every child patent in a family shares the parent’s term unless it carries PTA. The count of independent families is the better measure of how many different expiry dates exist. Platforms such as DrugPatentWatch organize Orange Book patents, expiration dates and Paragraph IV records so a team can build that family view without reading each document first. The primary records still decide the answer.
Questions to Ask of Each Patent
Four questions sort the estate: What is the earliest claimed filing date? Does the patent carry PTA or a terminal disclaimer? Is it listed in the Orange Book? Do its claims read on the proposed product? Entresto’s ‘918 patent failed the last test and had not passed the third [16].
What Should a Challenger Expect in Settlement Talks?
Expect the owner to point to the count. The Humira record shows that eight biosimilar makers settled and that only two disputes reached a court-defined patent list [12]. A challenger with a clear read of the family structure can price the risk by families and not by raw count. That is analysis, and each case turns on its own claims.
What Happens Next?
This section is a forecast and is labeled as such. Four pressures are in place. First, ODP law after Cellect and Allergan penalizes PTA in later-filed families [4][5]. Second, the fee schedule makes late continuations cost more [7]. Third, the USPTO’s terminal disclaimer rule is gone, so terminal disclaimers remain a tool with no new validity linkage [6]. Fourth, the Seventh Circuit found the Humira thicket lawful, so antitrust risk has not acted as a brake [11]. A reasonable expectation is that continuation filing will concentrate on claims aimed at specific products. Legislators and the USPTO could still reopen the terminal disclaimer question, and the Federal Circuit could refine Allergan. No source reviewed here predicts either event.
Key Takeaways
A continuation expires 20 years from the earliest claimed filing date. It cannot lengthen the family’s term [3].
Cellect counts PTA in ODP comparisons. Allergan shields the first-filed, first-issued patent in a family [4][5].
The January 19, 2025 surcharge is $2,700 at six years and $4,000 at nine years. It is small next to per-patent litigation cost [7][12].
AbbVie’s Humira estate was large: 247 applications by I-MAK’s count and 132 patents in the Seventh Circuit’s account [8][11].
The 2023 U.S. biosimilar date came from a settlement, about 73 months after the compound patent expired (calculation) [9][10].
Courts defined patent counts for only two Humira disputes, covering 16.4% and 10.8% of identified patents (calculation) [12].
Entresto’s later amorphous-form patent had a later expiry, but it was unlisted and lost on non-infringement in district court [15][16].
Continuations are best used for scope against known products and as a hedge, not for time.
FAQ
Does a Continuation Patent Get a New 20-Year Term?
No. The term runs 20 years from the earliest filing date the application claims under sections 120, 121, 365(c) or 386(c) [3].
Can a Continuation Patent Receive Patent Term Adjustment?
Yes, PTA exists under 35 U.S.C. 154. After In re Cellect, a patent’s PTA counts when a court measures ODP [4]. After Allergan v. MSN, the first-filed, first-issued patent in a family cannot be invalidated by a later-filed, later-issued continuation [5].
What Does a Terminal Disclaimer Do?
It gives up part of a patent’s term and ties the disclaimed patent’s enforceability to common ownership with the earlier patent [6].
Did the USPTO Adopt the 2024 Terminal Disclaimer Rule?
No. The USPTO proposed it on May 10, 2024 and withdrew it on December 4, 2024 [6].
How Much Is the Continuing Application Surcharge?
For large entities it is $2,700 for applications filed six or more years after the earliest benefit date and $4,000 at nine or more years. The fees took effect on January 19, 2025 [7].
Did the Humira Patent Thicket Violate Antitrust Law?
Not on the facts before the Seventh Circuit. On August 1, 2022 it affirmed dismissal of the claims and found the U.S. settlement was not a reverse-payment settlement [11].
How Many Patents Did AbbVie Hold on Humira?
It depends on the source and the date. I-MAK counted 247 applications in December 2018 [8]. The Seventh Circuit coverage records 132 patents in 2022 [11]. The counts measure different things and should not be compared directly.
When Could Amgen Launch a Humira Biosimilar in the United States?
The September 28, 2017 settlement set the U.S. license start at January 31, 2023. The EU start was October 16, 2018 [10].
Can a Later Patent on a New Form Outlast the Original Patent?
It can have a later expiry date. Entresto’s ‘918 patent was due to expire in November 2026, while the ‘659 patent’s protection ran to July 15, 2025 with pediatric exclusivity [15]. A later date does not guarantee protection. The ‘918 patent lost on non-infringement in district court [16].
What Should a Generic Developer Check First in a Large Patent Family?
Check the earliest claimed filing date, any PTA or terminal disclaimer, Orange Book listing and whether the claims read on the product. Entresto’s ‘918 patent was not listed and did not read on MSN’s product [16].
References
AbbVie Inc. (2023). Exhibit 99.1: AbbVie reports full-year and fourth-quarter 2022 financial results [Form 8-K]. U.S. Securities and Exchange Commission. https://www.sec.gov/Archives/edgar/data/1551152/000155115223000006/abbv-20221231xexhibit991.htm
AbbVie Inc. (2024). AbbVie reports full-year and fourth-quarter 2023 financial results. BioSpace. https://www.biospace.com/abbvie-reports-full-year-and-fourth-quarter-2023-financial-results
U.S. Patent and Trademark Office. (n.d.). Manual of Patent Examining Procedure, section 2701: Patent term. https://www.uspto.gov/web/offices/pac/mpep/s2701.html
WilmerHale. (2023, August 29). Patent term adjustments in jeopardy after In re Cellect. https://www.wilmerhale.com/en/insights/client-alerts/20230829-patent-term-adjustments-in-jeopardy-after-in-re-cellect
Gibson, Dunn & Crutcher LLP. (2024, August). Federal Circuit decision in Allergan v. MSN [Client alert]. https://gibsondunn.com/wp-content/uploads/2024/08/federal-circuit-decision-in-allergan-v-msn.pdf
Congressional Research Service. (2025, February 24). Terminal disclaimers of patent rights: Background and issues for Congress (LSB11209). https://www.everycrsreport.com/reports/LSB11209.html
Foley & Lardner LLP. (2024, November). USPTO publishes final fees for 2025. https://www.foley.com/insights/publications/2024/11/uspto-publishes-final-fees-2025/
I-MAK. (2018, December 18). Report finds 89% of total U.S. patent applications on Humira were filed after FDA approval, pointing to a deliberate strategy to delay competition. https://www.i-mak.org/2018/12/18/report-finds-89-of-total-u-s-patent-applications-on-humira-were-filed-after-fda-approval-pointing-to-a-deliberate-strategy-to-delay-competition/
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