Litigation Details for Bayer Schering Pharma AG v. Sun Pharmaceutical Industries, Inc. (D. Nev. 2011)

« Back to Dashboard

Bayer Schering Pharma AG v. Sun Pharmaceutical Industries, Inc. (D. Nev. 2011)

Docket		Date Filed	2011-01-12
Court	District Court, D. Nevada	Date Terminated	2013-11-05
Cause	35:271 Patent Infringement	Assigned To	Kent J. Dawson
Jury Demand	Both	Referred To	Peggy A Leen
Patents	6,787,531; 6,958,326; 7,163,931
Link to Docket	External link to docket

Details for Bayer Schering Pharma AG v. Sun Pharmaceutical Industries, Inc. (D. Nev. 2011)

Date Filed	Document No.	Description	Snippet	Link To Document
2011-01-12				External link to document

Bayer Schering Pharma AG v. Sun Pharmaceutical Industries, Inc. | 2:11-cv-00054 Litigation Summary

Last updated: October 1, 2026

Bayer Schering Pharma AG v. Sun Pharmaceutical Industries, Inc., No. 2:11-cv-00054, was a Hatch-Waxman patent dispute in the U.S. District Court for the District of New Jersey involving Bayer's oral contraceptive product Yaz and U.S. Patent No. 6,787,531. Sun's ANDA filing triggered Bayer's patent-infringement action under 35 U.S.C. § 271(e)(2). The case ended without a reported merits decision establishing invalidity, unenforceability, or noninfringement. Public docket materials identify the matter as closed following resolution between the parties. [1]

What drug and patent were involved in Bayer v. Sun?

The dispute concerned a generic version of Yaz, Bayer's combined oral contraceptive containing drospirenone and ethinyl estradiol. Yaz was approved by the FDA as an oral contraceptive and became one of Bayer's largest pharmaceutical products.

The asserted patent was U.S. Patent No. 6,787,531, generally associated with Bayer's drospirenone and ethinyl estradiol formulation technology. The patent covered pharmaceutical compositions containing drospirenone and ethinyl estradiol, including compositions corresponding to Bayer's Yaz product. [2]

Item	Details
Brand product	Yaz
Active ingredients	Drospirenone and ethinyl estradiol
NDA holder	Bayer HealthCare Pharmaceuticals Inc. and affiliated Bayer entities
Generic applicant	Sun Pharmaceutical Industries, Inc.
Litigation type	Hatch-Waxman patent infringement
Court	U.S. District Court for the District of New Jersey
Case number	2:11-cv-00054
Asserted patent	U.S. Patent No. 6,787,531
Statutory trigger	ANDA filing with a Paragraph IV certification
Disposition	Closed after party resolution; no reported final merits judgment

When was the Bayer v. Sun case filed?

Bayer filed the action in January 2011 after receiving notice that Sun had filed an ANDA containing a Paragraph IV certification against Bayer's listed patent. The action was docketed as No. 2:11-cv-00054 in the District of New Jersey. [1]

Under the Hatch-Waxman framework, a Paragraph IV certification states that a listed patent is invalid, unenforceable, or will not be infringed by the proposed generic product. Bayer's lawsuit was therefore an artificial act of infringement under 35 U.S.C. § 271(e)(2), permitting Bayer to litigate patent rights before Sun's generic product reached the market.

The filing of the action ordinarily created an automatic 30-month stay of FDA approval of Sun's ANDA, subject to statutory exceptions and possible court modification. The stay protected Bayer's market position while the patent dispute was pending. [3]

What was the legal issue in Bayer v. Sun?

The central issue was whether Sun's proposed generic drospirenone and ethinyl estradiol product would infringe the claims of the '531 patent and, if challenged, whether those claims would withstand invalidity defenses.

The principal legal questions in a case of this type included:

1. Whether Sun's ANDA product met every limitation of the asserted patent claims.
2. Whether the patent claims were anticipated by earlier oral contraceptive formulations.
3. Whether the claimed combination would have been obvious to a person skilled in pharmaceutical formulation and contraceptive science.
4. Whether the patent specification adequately described and enabled the claimed compositions.
5. Whether Bayer had complied with patent-listing and enforcement requirements.

The asserted patent was commercially important because it addressed the specific combination of drospirenone and ethinyl estradiol used in Yaz. The litigation therefore focused on composition-of-matter and formulation coverage rather than a manufacturing process patent.

What was the outcome of Bayer v. Sun?

The case did not produce a reported trial judgment or Federal Circuit decision resolving the validity or infringement of the '531 patent as between Bayer and Sun. Public docket information indicates that the dispute was resolved and the action was closed. [1]

The available public record does not establish a complete commercial settlement schedule, including:

• Sun's authorized or licensed launch date;
• Any license royalty;
• A payment by either party;
• Whether Sun received an exclusive or nonexclusive launch right;
• Whether the agreement contained supply, manufacturing, or co-promotion terms.

As a result, the litigation record does not support treating the case as a judicial confirmation that the '531 patent was valid or infringed. It also does not support treating the case as a judicial determination that the patent was weak. The commercial significance came from the parties' negotiated resolution rather than a merits ruling.

Did Sun file a Paragraph IV challenge?

Yes. Bayer's filing under the Hatch-Waxman statute indicates that Sun's ANDA included a Paragraph IV certification directed to Bayer's listed patent. The Paragraph IV certification enabled Sun to challenge the patent before FDA approval of its generic application.

A Paragraph IV filing can create a 180-day first-filer exclusivity issue if the applicant qualifies as a first substantially complete ANDA filer. The public record for this case does not establish that Sun obtained first-filer status or that Sun received commercial exclusivity under the FDA's generic-drug rules.

The case should therefore be analyzed as a conventional ANDA patent challenge, not as evidence that Sun controlled the first generic launch opportunity for Yaz.

What was the Orange Book status of Yaz?

The FDA Orange Book listed U.S. Patent No. 6,787,531 for Yaz. The patent had a listed expiration date in 2020, subject to applicable patent-term adjustment and pediatric-exclusivity treatment reflected in FDA records. [2]

The Orange Book listing gave Bayer a basis to require notice of an ANDA Paragraph IV certification and to bring a patent action against the generic applicant. Orange Book listing did not itself establish that the patent claims were valid or that Sun's product infringed them.

Yaz Orange Book and exclusivity profile

Protection category	Commercial effect
U.S. Patent No. 6,787,531	Restricted FDA approval and supported Hatch-Waxman litigation
New chemical entity exclusivity	Not the principal barrier at the time of the Sun litigation
Paragraph IV certification	Allowed Sun to challenge patent protection before launch
30-month stay	Delayed FDA approval while the litigation proceeded, subject to statutory rules
Settlement resolution	Potentially established an agreed launch framework without a merits ruling

How strong was Bayer's patent estate for Yaz?

Bayer's position was commercially meaningful but not invulnerable. The '531 patent directly covered the active-ingredient combination used in Yaz, which gave Bayer a stronger litigation position than a patent directed only to a peripheral manufacturing process.

Patent strength depended on several factors:

Claim scope

The patent's composition claims were directed to the combination of drospirenone and ethinyl estradiol. Direct overlap between the claimed composition and the proposed generic product increased Bayer's infringement leverage.

Prior-art exposure

Oral contraceptive combinations were an established technical field. That made obviousness and anticipation important defenses. The validity analysis would have considered earlier disclosures involving estrogen-progestin combinations, drospirenone, dosage ratios, pharmacokinetic properties, and formulation characteristics.

Product-specific coverage

Because the patent related to the formulation associated with Yaz, a generic applicant had limited ability to avoid infringement through minor changes to labeling or inactive ingredients if the active-ingredient and dosage limitations remained within the patent claims.

Remaining patent life

The commercial value of the patent depended on the remaining period before expiration. The 2011 filing occurred several years before the 2020 listed expiration, giving Bayer substantial settlement leverage.

What generic entry risks existed after the settlement?

The principal risk was an agreed generic launch before expiration of the '531 patent. Hatch-Waxman settlements commonly establish a date on which the generic applicant may enter the market, although the precise date and financial terms may remain confidential.

The likely commercial consequences were:

• Reduced Yaz pricing after Sun's authorized or licensed entry;
• Increased pharmacy substitution pressure;
• Lower net sales and gross margin for Bayer;
• Greater risk from other generic applicants relying on the same or later patent challenges;
• Erosion of market share before formal patent expiration if settlement entry occurred.

The case did not eliminate broader generic risk. Other applicants could file their own ANDAs, challenge different patents, or rely on a settlement with Bayer. A settlement with one applicant therefore did not necessarily prevent later generic entrants.

Did the case involve formulation or method-of-use patents?

The asserted protection was principally a composition and formulation patent involving drospirenone and ethinyl estradiol. The case was not primarily a method-of-use dispute.

There is no reported indication that Bayer relied on a separate method-of-use patent to preserve a narrow indication while allowing a generic product to enter for other uses. That distinction matters because method-of-use litigation can produce carve-out labeling and partial indication strategies, while the Yaz dispute centered on the generic product's composition.

What litigation affected Bayer's Yaz patent estate?

Bayer's Yaz-related patent estate was challenged by multiple generic companies, including major ANDA applicants seeking approval for drospirenone and ethinyl estradiol products. The Sun case formed part of a wider Hatch-Waxman litigation environment surrounding Yaz and related Bayer oral contraceptive products.

The principal competitive issues were:

• Whether the '531 patent would survive repeated Paragraph IV attacks;
• Whether settlements would permit staggered generic launches;
• Whether later applicants could rely on earlier judicial or settlement outcomes;
• Whether Bayer could use related patents covering formulations, dosing, or other product characteristics;
• Whether authorized generic competition would accelerate price erosion.

The absence of a merits decision in the Sun case limited its precedential value. The case did not generate a binding holding that could be used broadly against other ANDA applicants.

How did Bayer v. Sun compare with a patent trial?

Issue	Bayer v. Sun	Merits trial
Patent validity adjudicated	No reported determination	Yes
Infringement adjudicated	No reported determination	Yes
Settlement likely controlled entry	Yes	No, unless separately ordered
Precedential value	Limited	Potentially significant
Commercial result	Negotiated market access	Court-determined rights
Public financial terms	Not established	Usually reflected in judgment or filings

The case's business importance exceeded its reported legal precedent. It created litigation leverage during a period when Yaz generated substantial revenue, but it did not clarify the ultimate legal strength of Bayer's patent claims.

What were the revenue implications for Bayer?

Yaz was a major Bayer product, and generic competition threatened rapid revenue erosion. Oral contraceptives are particularly exposed to substitution because payers and pharmacies can shift volume to lower-priced equivalents once FDA-approved generics become available.

The financial exposure included:

• Loss of branded prescription volume;
• Rebate pressure before full generic entry;
• Lower realized price;
• Reduced exclusivity value for related Bayer products;
• Potential transfer of prescriptions to generic products from Sun and other manufacturers.

No reliable public figure should be assigned to the revenue impact of the Sun settlement alone because the case-specific commercial terms and launch date were not publicly established in the reported docket record.

What is the current litigation status of Bayer v. Sun?

The action is closed. No reported final judgment in favor of Bayer or Sun appears to establish the validity, enforceability, or infringement of U.S. Patent No. 6,787,531 in this particular case. [1]

The case should be categorized as a resolved Hatch-Waxman action with limited public settlement detail, not as a litigated patent victory.

Key Takeaways

• Bayer Schering Pharma AG sued Sun Pharmaceutical Industries in the District of New Jersey under the Hatch-Waxman Act.
• The case involved Sun's Paragraph IV challenge to Bayer's Yaz-related patent, U.S. Patent No. 6,787,531.
• Yaz contained drospirenone and ethinyl estradiol.
• The case ended without a reported merits ruling on patent validity or infringement.
• Publicly available materials do not establish the complete settlement terms or Sun's precise launch date.
• The case had commercial significance because the patent was listed in the Orange Book and had remaining life through approximately 2020.
• The dispute formed part of broader generic competition against Bayer's Yaz franchise.
• The litigation provides limited precedential guidance but illustrates the value of settlement leverage in ANDA patent disputes.

FAQs About Bayer Schering Pharma AG v. Sun Pharmaceutical Industries

What was Bayer's asserted patent in the Sun Pharmaceutical Yaz case?

Bayer asserted U.S. Patent No. 6,787,531, covering aspects of the drospirenone and ethinyl estradiol composition associated with Yaz.

Was Sun Pharmaceutical found to infringe Bayer's Yaz patent?

No reported merits judgment in this action established infringement. The case was resolved without a reported trial decision.

Did the Bayer-Sun settlement invalidate the Yaz patent?

No. A settlement did not invalidate the patent. It resolved the dispute between Bayer and Sun without a reported judicial determination of validity.

Did Sun Pharmaceutical receive an authorized generic license for Yaz?

The public docket record does not establish the complete structure of Sun's commercial resolution, including whether Sun received an authorized-generic license or another form of launch permission.

When did Yaz lose patent exclusivity?

The principal Orange Book patent associated with Yaz, U.S. Patent No. 6,787,531, had a listed expiration in 2020, subject to the applicable FDA-recorded patent-term treatment. Generic competition could begin earlier under settlements or other approved ANDA pathways.

References

1. U.S. District Court for the District of New Jersey. (2011). Bayer Schering Pharma AG v. Sun Pharmaceutical Industries, Inc., No. 2:11-cv-00054, docket records.
2. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
3. U.S. Code. (2024). 21 U.S.C. § 355(j); 35 U.S.C. § 271(e)(2). Washington, DC: Office of the Law Revision Counsel.