On December 20, 2024, the Federal Circuit affirmed an order that removed five Teva patents from the FDA Orange Book. [1] The patents covered parts of the ProAir HFA inhaler, such as the dose counter. None of them claimed the active ingredient, albuterol sulfate. [1] Listed patents are what make the 30-month stay of generic approval available. [2] Teva had listed patents that a court later said did not belong there.
This is the cost of a defend-everything portfolio. Each patent you assert needs money and a clean record. Each patent you list needs a legal basis that a regulator or a generic company can test. A weak patent does not sit quietly in the portfolio. It can lose in court, and it can create positions that hurt your strong patents.
This article argues that a brand manufacturer should rank its patents and defend the ones that earn it. It uses public records from the Federal Circuit, the FTC, the Seventh Circuit, the USPTO, and the Humira and Entresto litigation. It also uses DrugPatentWatch, a patent and generic-entry intelligence platform, as a starting point for inventory work. [18]
The Short Answer: Why Patent Triage Beats Defending Everything
Patent triage is the practice of ranking every patent in a drug’s portfolio by what it is worth in court and in the market. You then spend defense money on the patents at the top of the ranking. This definition is an original working definition for this article. It is not an established industry term.
What does patent triage mean in pharma IP?
Triage does not mean you give up patents. It means you decide, patent by patent, which of four actions applies: defend, maintain, cure or delist, or release. The framework in a later section defines each action and gives a scoring table. The framework is an original classification. It is not an industry standard.
The Five Findings That Matter
Each finding below can be read alone. Calculated figures are marked as analysis.
On December 20, 2024, the Federal Circuit held that an Orange Book patent must claim at least the active ingredient. It affirmed the delisting of five ProAir HFA device patents. [1][2]
The FTC disputed Orange Book listings for 37 products in two waves: 17 products in November 2023 and 20 products in April 2024. [7] As of July 2024, 6 of the 17 first-wave products had changed their listings. None of the 20 second-wave products had. [7] Analysis: 6 of 37 products is 16.2%.
I-MAK counted 247 US patent applications on Humira. It reported that 89% were filed after FDA approved the drug in 2002. [8] On August 1, 2022, the Seventh Circuit affirmed the dismissal of an antitrust case about the thicket. It held that amassing patents alone did not state a claim. [10]
In biosimilar litigation, AbbVie reportedly proceeded on 10 of 61 identified patents against Amgen. It proceeded on 8 patents against Boehringer Ingelheim. [11] Analysis: 10 of 61 patents is 16.4%.
The Federal Circuit reversed the written-description ruling on the Entresto ‘659 patent on January 10, 2025. [12] The patent expired five days later, on January 15, 2025. [12] On July 11, 2025, the district court found that Novartis had not proven that MSN infringed the separate ‘918 patent. [15]
The AIPLA 2023 survey, as reported by DrugPatentWatch, puts litigation through trial and appeal at about $1 million per patent in cases with $1 million to $10 million at risk. [11] Novartis reported more than $7.8 billion in Entresto sales in 2024. [13] Analysis: the fees on a ten-patent assertion are small next to the revenue at stake. The larger cost of a weak patent is risk, not fees.
How Did Drug Patent Portfolios Get This Big?
Why do drug makers file patents after approval?
Brands file after approval because products change. They add formulations, dosing regimens, manufacturing methods, and devices. A post-approval filing can claim a real improvement. The filing date alone does not prove intent.
The Humira record shows how large the effect can be. I-MAK reported the following figure in its Humira report. [8]
“89% of the total patent applications on Humira in the U.S. were filed after the drug was approved in 2002.” (I-MAK, 2021, p. 4) [8]
I-MAK also reported 247 US patent applications on Humira. [8] Its 2018 press release described the filing pattern as a deliberate strategy to delay competition. [9] That is I-MAK’s characterization. Courts have not adopted it, as the Seventh Circuit section below shows. [10]
What is the Orange Book and why does listing matter?
The Orange Book is FDA’s list of approved drugs and the patents that the brand says cover them. A listed patent must claim the drug for which the applicant submitted the application. [2] Under the statute, it must be a drug substance patent, a drug product patent, or a patent that claims a method of using the drug. [2]
FDA only receives this information from the NDA holder. It does not check whether each listing is proper. [2] This gap is why the FTC and generic companies now test listings from the outside.
Why does the 30-month stay create a defend-everything reflex?
A Hatch-Waxman lawsuit on a listed patent triggers an automatic 30-month stay of FDA approval of the generic. The stay applies whatever the merits of the infringement case. [2] One listed patent can therefore delay a generic by up to 30 months. A brand has a reason to list as many patents as it can support.
The reflex has a flaw. The stay depends on a valid listing. If a court orders a patent delisted, the basis for the stay on that patent goes with it. [2]
What a listing buys
A valid listing lets you sue a generic applicant on the listed patent and trigger the stay. [2] That is time, and time is revenue.
What a listing costs
A listing exposes the patent to a delisting counterclaim. A generic filer can ask a court to order delisting under 21 U.S.C. section 355(j)(5)(C)(ii)(I). [2] The listing also draws FTC attention if the patent is a device patent that does not claim the drug. [3][4]
Why Did Teva v. Amneal Change the Cost of Listing Weak Patents?
Teva v. Amneal made the listing rule concrete. The Federal Circuit read the statute narrowly. A patent must claim at least what made the product approvable as a drug, which is its active ingredient. [1][2]
Teva v. Amneal timeline
Date
Event
Source
June 10, 2024
D.N.J. (No. 2:23-cv-20964) finds five Teva inhaler patents improperly listed and orders them removed from the Orange Book. The FTC filed as amicus curiae in support of Amneal.
[6]
July 2024
The district court decision is stayed pending appeal, so the patents stay listed for the time being.
[6][7]
December 20, 2024
Federal Circuit (No. 2024-1936) affirms the delisting order.
[1][7]
What did the Federal Circuit hold on Orange Book listing?
The court held that a patent qualifies only if it claims at least the active ingredient. Eckert Seamans quotes the court as saying a patent must claim “at least what made the product approvable as a drug in the first place.” [2] The five patents claimed the dose counter and the canister. They did not claim albuterol sulfate. [2]
Teva argued that a patent qualifies if its claims cover the accused product. The court rejected that position. [2] Approval of a drug-device combination under an NDA does not turn the device components into the drug. [2]
What happens to the 30-month stay when a patent is delisted?
Delisting removes the basis for the stay on that patent. [2] The generic can then seek approval without waiting for the stay to run out. The Eckert Seamans analysis says delisting would clear the way for Amneal’s earlier approval and launch. [2]
Does delisting make a patent invalid or unenforceable?
No. Delisting does not remove a patent’s potential coverage of a proposed generic product. [5] A brand can still sue for infringement. It loses the Orange Book route to the stay.
Could the patents have been written to qualify?
Eckert Seamans suggests that a dependent claim reciting albuterol sulfate in the canister might have made the patents listable. [2] That point is a drafting lesson for new filings. It is the reason claim strategy belongs in the triage review and not only in prosecution.
The FTC Orange Book Campaign by the Numbers
Timeline of FTC warning-letter rounds
The FTC issued a policy statement in September 2023. It said improper Orange Book listings could be unfair methods of competition under Section 5 of the FTC Act. [3] Three rounds of warning letters followed.
Date
Scope
Source
September 2023
Policy statement: improper Orange Book listings may be unfair methods of competition under Section 5.
[3]
November 7, 2023
Warning letters to 10 manufacturers covering 17 brand-name products. More than 100 listings challenged.
[6][7]
April 30, 2024
Warning letters to 10 manufacturers covering 20 products. More than 300 patents disputed.
[5][7]
May 21, 2025
Warning letters to Novartis, Amphastar, Mylan Specialty, Covis, Norton (Waterford), and three Teva entities. More than 200 listings across 17 brand-name drugs.
[3][4]
What did brand manufacturers do in response?
Most did not change their listings in 2024. Polsinelli counted the outcomes after the FTC started Patent Listing Dispute proceedings at FDA for all 37 products. [7]
Wave
Products
Listings changed
Listings unchanged
Source
First (Nov. 2023)
17
6
11
[7]
Second (Apr. 2024)
20
0
20
[7]
Combined (analysis)
37
6 (16.2%)
31 (83.8%)
Calculated from [7]
Analysis: the response rate fell from 35.3% in the first wave (6 of 17) to 0% in the second wave. These counts are as of July 2024 and count products, not patents. Polsinelli’s authors called the initiative’s impact “minimal” at that date and wrote that FDA continues to rely on NDA holders’ information with little substantive review. [7]
Did the 2025 letters change the picture?
The May 21, 2025 round shows that the dispute did not end. The FTC told FDA that it disputes more than 200 listings. Most of them it had disputed before, and they remained in the Orange Book. [4] The Teva v. Amneal ruling gave the FTC a legal basis for the new round. [3]
How does the FDA dispute process work?
After FDA forwards a dispute, the brand has 30 days to withdraw or amend the listing. The other choice is to certify, under penalty of perjury, that the listing complies with the requirements. [5] A certification puts the executive who signs it on the record.
What does this mean for a portfolio review?
Every listed device, delivery-system, or packaging patent needs a documented answer to one question: does a claim recite the active ingredient? If the answer is no, the listing is a risk with little benefit after Teva v. Amneal. [1][2]
Case Study: Humira and the Cost of Holding 100+ Patents
What did the Humira patent estate look like?
I-MAK counted 247 US patent applications on Humira. [8] The Seventh Circuit opinion summary says AbbVie obtained 132 additional Humira patents after the original patent expired. [10] The two numbers come from different sources and measure different things. One counts applications. The other counts granted patents after expiry. Do not divide one by the other.
Did the Seventh Circuit say patent thickets are illegal?
No. In Mayor and City Council of Baltimore v. AbbVie Inc., No. 20-2402, the Seventh Circuit affirmed dismissal of the complaint on August 1, 2022. The panel was Judges Easterbrook, Wood, and Kirsch. [10]
The court held that amassing patents alone did not state a Section 2 monopolization claim. The plaintiffs would have needed to show that the patents were invalid. [10] On the Section 1 claim, the court held that the plaintiffs did not show AbbVie overpaid competitors to delay entry. [10]
The result matters for triage. A large portfolio is not illegal. It is also not free. The ruling says you can hold the patents. It does not say each patent is worth defending.
How many Humira patents did AbbVie assert?
DrugPatentWatch’s analysis of the biosimilar litigation reports that AbbVie proceeded on 10 of 61 identified patents against Amgen. Against Boehringer Ingelheim, it proceeded on 8 patents. The portfolio exceeded 100 patents. [11] That analysis cites court and company filings. Confirm any figure you plan to quote against the dockets.
Analysis: 10 of 61 is 16.4%. The company with the largest portfolio in this record asserted a small share of it. AbbVie triaged in practice, even if it did not use the word.
What the pruning shows
A brand picks its best patents once a real opponent is in the room. The other patents stay in the portfolio and cost maintenance fees and attention. They do not carry the case.
Will Congress limit how many patents a brand can assert?
The Senate approved the Affordable Prescriptions for Patients Act by unanimous vote. The bill caps how many patents a drug maker can assert in litigation over individual biological products. Senator John Cornyn sponsored it. [17] The source article gives no numerical cap and no calendar date. This article did not confirm the bill’s current status after that source.
Case Study: Entresto and the Patent That Mattered
Entresto litigation timeline
Date
Event
Source
2015
FDA approves Entresto (sacubitril/valsartan).
[13]
2019
Novartis sues 18 generic drug makers over the ‘659 patent. The cases are consolidated in D. Del. (MDL No. 1:20-md-02930).
[14]
October 2022
Novartis asserts the ‘659 and ‘918 patents against MSN in D. Del.
[13]
July 7, 2023
The district court finds the ‘659 patent lacks written description.
[14]
January 10, 2025
Federal Circuit reverses the written-description ruling and affirms that the claims were not shown invalid for obviousness or lack of enablement.
[12]
January 15, 2025
The ‘659 patent expires. Pediatric exclusivity extends protection by six months.
[12]
July 11, 2025
After a four-day bench trial, the district court finds Novartis did not prove MSN infringes the ‘918 patent.
[15]
July 22, 2025
Federal Circuit lifts the temporary injunction on the ‘918 patent.
[14]
Late July 2025
Multiple generic versions launch.
[14]
What did the Entresto ‘659 ruling decide?
The Federal Circuit decided Novartis v. Torrent on January 10, 2025. It treated the written-description question as one about the claims. In the court’s words, as quoted by Fish & Richardson, “[b]ecause the ‘659 patent does not claim valsartan-sacubitril complexes, those complexes need not have been described.” [14]
The court also said the district court “erroneously conflated the distinct issues of patentability and infringement.” [12] The ‘659 patent was the core patent. It won its appeal on a precise legal question.
Why did the win come so late?
Analysis: Novartis first sued in 2019 and got its appeal result on January 10, 2025. That is more than five years. The patent then expired five days later. [12][14] Pediatric exclusivity added six months of protection. [12] A strong patent still delivers value on a clock, and the clock does not wait for the appeal.
What happened to the ‘918 patent?
The ‘918 patent claims an amorphous solid form of sacubitril, valsartan, and sodium cations. Its priority date is April 4, 2006. [15] The district court found that the Raman spectrum evidence from Novartis’s expert was not reliable. It held that Novartis had not proven infringement. [15]
Analysis: Novartis asserted the ‘918 patent against MSN in October 2022. The ruling came in July 2025, about two years and nine months later. [13][15] The patent had a late expiry date, November 9, 2026, according to IP Fray. [13] The late expiry date made it look valuable. The proof problem made it weak.
What did Fish & Richardson say to learn from Entresto?
Fish & Richardson drew several lessons from the case. Claim construction cuts both ways: a construction of “in combination” helped on infringement but created validity exposure. Test each construction against every claim and defense. Weigh the forum choice by past success rates, time to resolution, and cost. Plan for a long case with parallel proceedings, new patents, stays, and appeals. [14]
What does Entresto show about triage?
A portfolio holds patents with different jobs. The compound-level patent carried the case. The form patent depended on a spectrum comparison that the court did not accept. A triage review would have scored the form patent’s infringement proof before the trial, not after it.
What Does Patent Litigation Cost Per Patent?
AIPLA 2023 cost benchmarks, as reported
DrugPatentWatch reports AIPLA 2023 figures for litigation cost, by amount at risk. It describes them as per patent, per side, and based on a single defendant. [11] I did not check the AIPLA report itself. The figures cover all patent technology areas, not only pharmaceutical patents. [11]
Amount at risk
Through discovery and claim construction
Through trial and appeal
Under $1 million
about $300,000
about $600,000
$1 million to $10 million
about $600,000
about $1 million
$10 million to $25 million
about $1.5 million
about $3 million
Source: AIPLA 2023 Report of the Economic Survey, as summarized in [11].
Scenario analysis: a hypothetical 40-patent portfolio
The scenario below is an illustration. It does not describe a real company or drug. It uses the $1 million to $10 million at-risk band from the table above.
Assumptions
The brand holds 40 patents on one product. The brand faces one generic defendant. Cost is $600,000 per patent through discovery and claim construction, and $1 million per patent through trial and appeal. The model ignores win probability, settlement, and consolidation savings.
Results
Strategy
Patents asserted
Cost through claim construction
Cost through trial and appeal
A: Assert everything
40
$24.0 million
$40.0 million
B: Assert the top 10
10
$6.0 million
$10.0 million
C: Assert the top 6
6
$3.6 million
$6.0 million
Analysis: Strategy B saves $30.0 million through trial and appeal, which is 75% of Strategy A. Strategy C saves $34.0 million, which is 85%.
Are legal fees the real cost of defending every patent?
For a blockbuster, fees are the smaller cost. Novartis reported more than $7.8 billion in Entresto sales in 2024. [13] Analysis: that is about $650 million per month on average. One month of those global sales equals the through-trial cost of 650 patents at the $1 million benchmark.
The comparison shows scale. It is not a return calculation. Sales are not profit, the US share is lower than the global figure, and generic erosion is not linear. The point is that the fee savings in Strategy B are not the main reason to triage.
The main reasons are risk reasons. A weak patent can set a claim construction that a strong patent must live with. [14] A weak listing can bring an FTC dispute. [3][4] A weak patent can lose at trial and give the generic company a public record.
A Four-Tier Patent Triage Framework
The framework below is an original classification. It is not an established industry classification. It sorts patents into four actions.
Tier 1: Defend
Tier 1 patents are the ones you assert first and fund fully. They usually claim the drug substance or the approved product, have a clean validity record, and expire late enough to matter. The Entresto ‘659 patent fits this tier. It claimed the core compound and survived its appeal. [12]
Tier 2: Maintain
Tier 2 patents stay in force and stay in reserve. You pay the maintenance fees. You do not assert them unless the facts change. A formulation patent that a generic can design around is a common example.
Tier 3: Cure or delist
Tier 3 patents carry listing risk or proof risk. A device patent that does not recite the active ingredient belongs here after Teva v. Amneal. [1][2] You can cure the problem with a new claim strategy where the law allows it. [2] If you cannot cure it, you delist before a court or the FTC forces the issue.
Tier 4: Release
Tier 4 patents cost more to hold than they return. You let them lapse at a maintenance window. The statute says a patent expires at the end of the grace period if the fee is not paid. [16] Release is a decision with a date, and the dates are known in advance.
Triage scoring table
Score each patent from 1 (weak) to 5 (strong) on each criterion. A low score on listability or infringement proof moves a patent down a tier, whatever its other scores.
Criterion
Question to answer
Evidence to pull
Listability
Does a claim recite the active ingredient, or claim an approved method of use?
Claims; Orange Book entry [1][2]
Validity exposure
Which grounds can a generic company argue, and how have courts treated similar claims?
Prior art; written-description and enablement risk [12]
Infringement proof
Can you prove infringement with reliable evidence against a real ANDA product?
Test data; expert plan [15]
Design-around risk
Can a generic avoid the claim at low cost?
Claim scope; product differences
Remaining term
How long does the patent last, counting any extension?
Expiry date; pediatric exclusivity [12]
Cross-case risk
Does asserting this patent require a claim construction that hurts a stronger patent?
Claim construction positions [14]
When Should You Pay the Maintenance Fee? Decision Points at 3.5, 7.5, and 11.5 Years
What are the USPTO maintenance fee deadlines?
The statute sets three maintenance fees. They fall due three years and six months, seven years and six months, and eleven years and six months after grant. [16] Each deadline is a scheduled triage decision. Put the three dates on the calendar for each patent when it issues.
Decision point
Due after grant
Triage question
First
3 years 6 months
Does the patent still match the product that FDA approved or that you plan to sell?
Second
7 years 6 months
Has any court or the PTAB treated a related claim badly?
Third
11 years 6 months
Will the patent still add exclusivity before generic entry?
The USPTO adjusts the fee amounts. Check the current schedule before you decide.
What happens if you miss a maintenance fee window?
A patent owner has a grace period of six months after the due date. If the fee is not received by the end of the grace period, the patent expires at the end of that period. [16]
Is letting a patent lapse a concession?
No. A lapse is a documented business decision. A patent that no longer protects a product, or that you cannot enforce, does not add exclusivity. It adds cost, and it adds a claim set that a generic company can attack.
Does lapse affect the other patents?
A lapse on one patent does not change the term of another patent. Check that no pending continuation or related claim depends on the same position before you let a patent go. This check belongs to your patent counsel.
What Does Triage Mean for Each Player?
What this means for brand manufacturers
A brand should run a listing audit first. The test is simple: list each patent, and write down which claim recites the active ingredient or the approved method of use. Patents that fail the test need a cure or a delisting plan. [1][2] In May 2025, the FTC told FDA that it disputes more than 200 listings, most of which it had disputed before. [4]
A brand should then rank the remaining patents. It should assert the top group first. The Humira and Entresto records show that a few patents carry the case. [10][11][12]
What this means for generic entry
A generic company should read each Orange Book listing as a claim to test. If a device patent does not recite the active ingredient, a delisting counterclaim is available under 21 U.S.C. section 355(j)(5)(C)(ii)(I). [2] Teva v. Amneal shows that the counterclaim can succeed. [1]
A generic company should also plan for patents beyond the first listed patent. A form patent, such as the Entresto ‘918 patent, can still matter after the core patent expires. [13][15]
What this means for biosimilar developers
A biosimilar developer faces portfolios like the Humira portfolio. [8] The Seventh Circuit decision means you cannot count on an antitrust claim to clear the path. [10] The practical route is patent-by-patent analysis. DrugPatentWatch’s reported Humira counts show how few patents reached litigation. [11]
What this means for investors and analysts
Patent counts alone do not measure protection. A portfolio of 100 patents may rest on a handful of claims. Look for which patents a brand has asserted, which are Orange Book listed, and which have faced a court. The Entresto record shows that the value of a portfolio can sit in one patent that expires on a known date. [12]
Who is exposed if triage is done badly?
Brands with device-heavy listings are exposed to delisting and FTC letters. [3][4][7] Brands with large post-approval portfolios are exposed to the cost of asserting weak patents. Generic companies are exposed if they assume a delisted patent cannot be asserted. It can. [5]
How to Run a Patent Triage Review in Six Steps
Step 1: Build the patent inventory
List every patent on the product, with grant date, expiry date, and Orange Book status. DrugPatentWatch tracks patents, generic entry, and litigation, and its page names the USPTO, the FDA Orange Book, ANDA filings, and litigation records among its sources. [18] Use a platform like this to build the first list. Confirm each patent against the USPTO record and the Orange Book before you rely on it.
Step 2: Test every listing against the statute
For each listed patent, find the claim that recites the active ingredient or claims an approved method of use. [2] Record the claim number. If you cannot find one, flag the patent for Tier 3.
Step 3: Map the litigation record
List each court ruling that touched the patent or a related claim. Note which claim constructions the brand has taken in any parallel case. [14] A construction that helps in one case can hurt in another.
Step 4: Score each patent
Use the six-criterion table in the framework section. Write a one-line reason for each score. A reviewer in six months will want the reason, not only the number.
Step 5: Set the assertion list and the reserve list
Choose the patents you will assert first. Choose the ones you will keep in reserve. Record the reasons. If a real opponent changes the facts, revisit the list.
Step 6: Calendar the decision dates
Put the three maintenance windows for each patent on a shared calendar. [16] Add the expiry dates, and add any exclusivity dates that extend them. [12] A triage review is only useful if the dates drive action.
Methodology and Limitations
What data did this article use?
The article uses public reporting and legal analysis of court decisions, FTC actions, and USPTO rules. It covers events from 2015 to July 2025. Sources were reviewed on November 1, 2026. Court and agency actions are cited through law-firm and trade analyses where the primary documents were not directly reviewed. The reference list shows each source.
How were the calculations done?
All calculated figures are marked as analysis. They use simple division and multiplication on the cited numbers. Examples: 6 divided by 37 gives 16.2%; 10 divided by 61 gives 16.4%; $7.8 billion divided by 12 gives about $650 million; 40 patents times $600,000 gives $24.0 million. The 40-patent scenario is hypothetical and uses stated assumptions.
What are the limits?
FTC outcome counts are as of July 2024 and count products, not patents. [7]
The AIPLA cost figures are quoted from DrugPatentWatch’s summary. They cover all patent technology areas. [11]
The Humira assertion counts come from a DrugPatentWatch analysis that cites court and company filings. [11]
Fish & Richardson reports that MSN filed a certiorari petition in late August 2025 (No. 25-225). This article did not find the outcome. [14]
This article did not confirm the current status of the Affordable Prescriptions for Patients Act. [17]
The article does not give legal advice. Consult patent counsel before you list, delist, or release a patent.
Key Takeaways
The Federal Circuit held on December 20, 2024 that an Orange Book patent must claim at least the active ingredient. [1][2]
The FTC disputed listings on 37 products in 2023 and 2024. Only 6 changed their listings as of July 2024. [7]
In May 2025, the FTC told FDA that it disputes more than 200 listings, most of which it had disputed before. [4]
The Seventh Circuit held that amassing patents alone does not state an antitrust claim. [10]
AbbVie reportedly asserted 10 of 61 identified patents against Amgen. [11]
The Entresto ‘659 patent won its appeal five days before it expired. [12]
The Entresto ‘918 patent lost on infringement proof on July 11, 2025. [15]
Three USPTO maintenance windows give a dated triage decision for every patent. [16]
FAQ
What is patent triage in pharma?
Patent triage is the ranking of a drug’s patents by court value and market value, followed by a decision to defend, maintain, cure or delist, or release each one. It is an original working definition used in this article, not an industry standard.
Can a brand list a device patent in the Orange Book?
Only if the patent claims at least the active ingredient. The Federal Circuit affirmed the delisting of five ProAir HFA device patents because none claimed albuterol sulfate. [1][2]
Does delisting a patent make it invalid?
No. Delisting does not remove a patent’s potential coverage of a proposed generic product. [5] It removes the Orange Book basis for the 30-month stay on that patent. [2]
What does the 30-month stay do?
A Hatch-Waxman lawsuit on a listed patent triggers an automatic 30-month stay of FDA approval of the generic, whatever the merits of the infringement case. [2]
Did the FTC succeed in getting patents delisted?
Partly. In the first wave, 6 of 17 products changed their listings. In the second wave, none of 20 did, as of July 2024. [7] The FTC sent a third round of letters on May 21, 2025. [3]
Is a patent thicket illegal?
The Seventh Circuit held in the Humira case that amassing patents alone did not state a monopolization claim. The plaintiffs would have needed to prove the patents were invalid. [10]
How many patents should a brand assert?
No rule sets a number. The reported Humira record shows AbbVie proceeding on 10 patents against one biosimilar developer and 8 against another, from a portfolio of more than 100. [11] A Senate-passed bill would cap assertions in biologic litigation, but the source gives no number. [17]
Why did the Entresto ‘918 patent lose?
The district court found that the Raman spectrum evidence from Novartis’s expert was not reliable. It held that Novartis had not proven MSN infringed the patent. [15]
When can a patent be released without penalty?
At a maintenance window. The patent expires at the end of the six-month grace period if the fee is not paid. [16] Ask patent counsel to check related claims before you let any patent lapse.
How can DrugPatentWatch help with a triage review?
DrugPatentWatch tracks patents, generic entry, and litigation, and it names the USPTO, the Orange Book, ANDA filings, and litigation records among its sources. [18] Use it to build the inventory, then verify each patent against the primary record.
References
Crowell & Moring LLP. (n.d.). Only drugs allowed: Federal Circuit affirms order to delist device patents from the Orange Book. https://crowell.com/en/insights/client-alerts/only-drugs-allowed-federal-circuit-affirms-order-to-delist-device-patents-from-the-orange-book
Eckert Seamans Cherin & Mellott, LLC. (n.d.). To be listable in the FDA’s “Orange Book,” patents must recite the API in claims. https://www.eckertseamans.com/legal-updates/to-be-listable-in-the-fdas-orange-book-patents-must-recite-the-api-in-claims
TechTarget. (2025, May 30). FTC targets 200 Orange Book patents to boost generic drug access. https://www.techtarget.com/pharmalifesciences/news/366624851/FTC-targets-200-Orange-Book-patents-to-boost-generic-drug-access
FDA Law Blog. (2025, June 9). Here FTC goes again on its own. https://www.thefdalawblog.com/2025/06/here-ftc-goes-again-on-its-own/
DLA Piper. (2024, May). FTC continues to scrutinize Orange Book patent listings. https://www.dlapiper.com/insights/publications/2024/05/ftc-continues-to-scrutinize-orange-book-patent-listings
White & Case LLP. (n.d.). The current status of FTC’s Orange Book listings challenge: A mixed bag. https://www.whitecase.com/insight-our-thinking/current-status-ftcs-orange-book-listings-challenge-mixed-bag
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