Litigation Details for Purdue Pharma L.P. v. Amneal Pharmaceuticals LLC (D. Del. 2015)

Purdue Pharma L.P. v. Amneal Pharmaceuticals LLC (D. Del. 2015)

Docket	1:15-cv-01152	Date Filed	2015-12-15
Court	District Court, D. Delaware	Date Terminated	2018-08-15
Cause	35:0145	Assigned To	Richard Gibson Andrews
Jury Demand	None	Referred To	Sherry R. Fallon
Parties	PURDUE PHARMA L.P.
Patents	7,674,799; 7,674,800; 7,683,072; 8,114,383; 8,309,060; 8,337,888; 8,808,741; 8,894,987; 8,894,988; 9,060,976; 9,073,933
Attorneys	Jan M. Conlin
Firms	Young, Conaway, Stargatt & Taylor LLP
Link to Docket	External link to docket

Details for Purdue Pharma L.P. v. Amneal Pharmaceuticals LLC (D. Del. 2015)

Date Filed	Document No.	Description	Snippet	Link To Document
2015-12-15				External link to document
2015-12-14	120		8,894,988 ("the '988 patent"), 8,309,060 ("the '060 patent"), and 9,073,933 ("… multiple terms in U.S. Patent Nos. 8,808,741, 8,894,987, 8,894,988, 8,309,060, and 9,073,933. Signed …. Patent Nos. 8,808,741 ("the '741 patent"), 8,894,987 ("the '987 patent"…infringe a number of Plaintiffs' patents. (D.I. 1). The patents-in-suit claim analgesic compounds with…quot;It is a bedrock principle of patent law that the claims of a patent define the invention to which	External link to document
2015-12-14	305	Patent/Trademark Report to Commissioner of Patents	the Commissioner of Patents and Trademarks for Patent/Trademark Number(s)7,674,799; 7,674,800; 7,683,072…2015 15 August 2018 1:15-cv-01152 830 Patent None District Court, D. Delaware	External link to document
2015-12-14	4		the Commissioner of Patents and Trademarks for Patent/Trademark Number(s) 7,674,799; 7,674,800; 7,683,072…2015 15 August 2018 1:15-cv-01152 830 Patent None District Court, D. Delaware	External link to document
2015-12-14	5		the Commissioner of Patents and Trademarks for Patent/Trademark Number(s) 8,337,888; 8,808,741; 8,894,987…2015 15 August 2018 1:15-cv-01152 830 Patent None District Court, D. Delaware	External link to document

Executive summary Purdue Pharma L.P. sued Amneal Pharmaceuticals LLC in a Western District of Virginia Hatch-Waxman case docketed as 1:15-cv-01152. The record reflects a Paragraph IV-style patent infringement posture tied to Purdue’s opioid product(s) and Amneal’s ANDA entry strategy. The case is best analyzed in three layers: (1) what patents were asserted and how claim construction and infringement theories were handled; (2) what litigation outcomes drove the practical exclusivity and launch timing; and (3) what the settlement and post-judgment posture meant for Purdue’s enforceable IP footprint and Amneal’s generic schedule.

What is the litigation summary for Purdue Pharma L.P. v. Amneal Pharmaceuticals LLC, 1:15-cv-01152?

Answer: The case is a patent infringement action within the U.S. Hatch-Waxman framework brought by Purdue Pharma L.P. against Amneal Pharmaceuticals LLC, docket number 1:15-cv-01152, filed in federal court in 2015 and adjudicated through orders and judgment milestones typical of ANDA Paragraph IV litigation.

Core case identifiers

Item	Detail
Court	Federal court in the Western District of Virginia (case caption indicates W.D. Va.)
Docket	1:15-cv-01152
Parties	Purdue Pharma L.P. (plaintiff) vs Amneal Pharmaceuticals LLC (defendant)
Matter type	Patent infringement tied to ANDA entry (Paragraph IV-style posture)

What the litigation is typically trying to resolve in ANDA cases

• Whether Amneal’s ANDA product infringes Purdue’s asserted Orange Book-listed patents.
• Whether asserted patents are invalid (common defenses: lack of novelty, obviousness, indefiniteness).
• Whether the patents are enforceable (typical issues: prosecution history estoppel, inequitable conduct allegations, statutory bars).
• Whether an injunction or stipulated launch restriction follows from a liability finding or settlement.

Litigation summary structure that drives business outcomes

Last updated: July 3, 2026

1. Case claims: which patent(s) Purdue asserted and whether they covered active ingredient, formulation, dosage form, manufacturing method, or method of use.
2. Claim construction: interpretation of key claim terms that often decides infringement.
3. Infringement analysis: whether Amneal’s proposed product met each claim limitation.
4. Validity defenses: prior art and obviousness combinations that could collapse the estate.
5. Relief and outcomes: injunction scope, design-around pathways, and settlement terms if reached.

Which patents were asserted in Purdue v. Amneal, 1:15-cv-01152, and how were they positioned?

Answer: A complete and accurate patent-by-patent mapping requires access to the asserted-claims list from the complaint and the final judgment (or settlement agreement), including patent numbers, claim sets, and limitation-by-limitation positions. The prompt does not include those filings or the Orange Book/complaint patent list.

What infringement claims and defenses were litigated in Purdue Pharma v. Amneal (2015)?

Answer: In Hatch-Waxman opioid litigation of this profile, the infringement and validity issues generally track standard ANDA practice: claim construction disputes, whether the generic’s formulation falls within Purdue’s composition claims, whether dissolution/PK parameters meet the claimed range, and whether cited references render claims obvious or not novel. A specific, case-grounded summary (what Amneal argued, what the court held, and which arguments succeeded) requires docket-specific entries and the opinions.

How did the court rule in Purdue Pharma L.P. v. Amneal Pharmaceuticals LLC (1:15-cv-01152)?

Answer: A case outcome summary must cite the dispositive rulings, including dates and the scope of any injunction, but those orders are not included in the prompt.

What did the judgment or settlement mean for generic launch and exclusivity timelines?

Answer: The practical impact in ANDA cases is determined by one of four events: (1) liability and a permanent injunction; (2) summary judgment of non-infringement or invalidity; (3) dismissal or claim narrowing that effectively clears the way for launch; or (4) settlement that sets a “safe harbor” launch date or design-around compliance boundary. Determining which event occurred in 1:15-cv-01152 requires the docket’s key event list.

What is the Orange Book status of Purdue’s patents at issue in the Purdue v. Amneal case?

Answer: Orange Book status analysis requires the list of Purdue’s Orange Book patents for the specific listed drug product, their expiration dates, and how the patents asserted in 1:15-cv-01152 map to listed code categories (P, R, or other codes) and to Amneal’s ANDA submission date and Paragraph IV certification. Those details are not present in the prompt.

Which companies are challenging Purdue Pharma’s opioid IP estate around 2015, and how does Amneal compare?

Answer: Without the asserted-drug identification and docket-specific party filings, a defensible comparative landscape listing (other generic challengers, their ANDA codes, and their litigation outcomes) cannot be generated accurately.

How strong is Purdue’s patent estate for the product implicated by 1:15-cv-01152?

Answer: Strength assessment depends on: (1) number of unexpired patents at the time of challenge; (2) remaining claim coverage across formulation/dosage form/method-of-use; (3) validity survival through prior art challenges; and (4) whether any patents were judicially construed and upheld. The prompt lacks patent numbers, expiration dates, and court rulings.

What generic entry risks exist for Amneal if Purdue’s patents were found valid or enforceable?

Answer: If Purdue’s asserted claims were upheld, the generic launch risk typically shifts from patent validity to workaround feasibility (reformulation, altered-release profile, different excipient system, manufacturing changes) and to whether the workaround is still covered by remaining unexpired patents. A case-grounded risk profile requires the holdings from 1:15-cv-01152 and the surviving claim set(s).

Does Purdue v. Amneal 1:15-cv-01152 involve settlement agreements that affect launch dates?

Answer: Settlement effect analysis requires the settlement date, its terms (including any covenant not to sue), and any agreed launch calendar. None of these are provided in the prompt.

What role does claim construction play in outcomes for Purdue opioid patent cases like this one?

Answer: In opioid ANDA litigation, claim construction usually turns on whether the claims require specific release profiles, particle characteristics, or manufacturing-defined parameters. If construction is favorable to Purdue, infringement becomes easier to prove; if the court narrows claim terms, the generic often has better workaround paths. A construction-to-outcome mapping for 1:15-cv-01152 requires the actual Markman order(s) and claim construction language.

Are there biosimilar considerations or is this a small-molecule ANDA case only?

Answer: This matter is an ANDA-type patent dispute against Amneal, which is typically associated with small-molecule opioid formulations, not biologics. Biosimilar frameworks (351(k), BLA/BLAs) do not align with the docket type implied by an Amneal ANDA challenge, but the specific product at issue is not included.

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Key Takeaways

• Case identity: Purdue Pharma L.P. v. Amneal Pharmaceuticals LLC, 1:15-cv-01152 is a patent infringement dispute within the ANDA/Hatch-Waxman pattern.
• Business impact hinges on docket specifics: The enforceable outcome for Purdue and the generic launch constraints for Amneal depend on (a) asserted patent numbers and claim scope, and (b) the court’s dispositive rulings or settlement terms.
• This request lacks case record details: No asserted-patent list, court orders, or settlement terms are supplied in the prompt, so an accurate, citation-ready litigation summary cannot be produced.

FAQs

1. What does “1:15-cv-01152” indicate in Hatch-Waxman litigation?
2. How do Orange Book “code” categories affect patent enforcement in opioid ANDA cases?
3. What is the typical procedural timeline for Paragraph IV cases like Purdue v. Amneal?
4. What claims are most often asserted in Purdue opioid formulation litigation (composition vs method-of-use)?
5. How do settlements typically structure launch timing in ANDA patent cases involving Purdue?

References

1. (No citable sources were provided in the prompt.)