Nexus Concordat
⚖️ Essential Case Law
Supreme Court & Federal Circuit Precedents for Patent Bar
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Fractured Crown: The Binding Precedents

Even as Guardian Queen Examiner, Athelia is not the highest authority. Above her sit the courts—first the Patent Trial and Appeal Board (PTAB), then the Court of Appeals for the Federal Circuit (CAFC), and at the apex, the Supreme Court of the United States.

These cases are binding precedents—rulings that Athelia must follow in every examination. When KSR declared that "common sense" and "predictable results" can support obviousness rejections, every examiner (including Athelia) gained new power to reject claims without needing explicit teaching in prior art. When Alice/Mayo established the two-step test for § 101 eligibility, abstract ideas became far easier to reject, devastating business method and software patents.

Supreme Court cases (highlighted in red borders) are the most powerful. They set the framework, the tests, the standards that govern all patent law:

KSR (§ 103 obviousness): Common sense, predictable results, obvious to try. The six KSR rationales are Athelia's toolkit for rejection.

Alice/Mayo (§ 101 eligibility): The two-step test. Abstract ideas, laws of nature, natural phenomena—all ineligible unless integrated into practical application or providing "significantly more."

eBay (remedies): Injunctions are not automatic. Four-factor equity test applies.

Federal Circuit cases (highlighted in blue borders) provide detailed application of Supreme Court principles. Ariad (written description), Therasense (inequitable conduct), Phillips (claim construction)—these cases fill in the gaps, showing how the high-level rules apply to specific fact patterns.

For the Patent Bar exam, you must know these cases cold. Not just the holdings, but the reasoning, the tests, the factors. The exam will present fact patterns requiring you to apply KSR rationales, Alice/Mayo framework, or eBay factors. Miss these, and you'll fail the exam.

These are the ancient laws binding Athelia's authority. Learn them. Master them. They are non-negotiable.

🏛️ Supreme Court Cases (Critical)

KSR Int'l Co. v. Teleflex Inc.
550 U.S. 398 (2007)
§ 103 Obviousness Motivation to Combine

📜 Holding:

Obviousness analysis cannot be confined to rigid formulas. The TSM (teaching, suggestion, motivation) test is helpful but not exclusive. Common sense and ordinary innovation can support obviousness even without explicit teaching in prior art.

KSR Rationales for Obviousness:

  • Combining prior art elements according to known methods to yield predictable results
  • Simple substitution of one known element for another to obtain predictable results
  • Use of known technique to improve similar devices in the same way
  • "Obvious to try" - choosing from finite number of identified, predictable solutions with reasonable expectation of success
  • Known work in one field prompts variations of it for use in same/different field if design need or market forces predictable
  • Teaching, suggestion, or motivation exists in prior art, knowledge of PHOSITA, or nature of problem itself

🎯 Exam Tips:

KSR allows common sense as rationale for combining references. Examiner can use "ordinary innovation," "predictable results," or "obvious to try" without needing explicit teaching. However, examiner must still provide some articulated reasoning - cannot just say "obvious" without explanation.

⚠️ Impact on Practice:

Made it easier for USPTO to reject claims as obvious. Applicants must show combination is NOT predictable, or argue secondary considerations (commercial success, long-felt need, failure of others).

Alice Corp. v. CLS Bank Int'l
573 U.S. 208 (2014)
§ 101 Eligibility Abstract Ideas

📜 Holding:

Claims directed to abstract idea of intermediated settlement are patent-ineligible. Implementing abstract idea on generic computer does not transform it into patent-eligible subject matter. Applied Mayo two-step framework to computer-implemented inventions.

Alice/Mayo Two-Step Test:

  • Step 1: Is claim directed to patent-ineligible concept (abstract idea, law of nature, natural phenomenon)?
  • Step 2A (Prong 1): Does claim recite judicial exception?
  • Step 2A (Prong 2): Is judicial exception integrated into practical application?
  • Step 2B: If not practical application, does claim provide significantly more than exception itself?

🎯 Exam Tips:

Abstract ideas: fundamental economic practices, methods of organizing human activity, mathematical concepts. Not enough: "apply it on computer" or "via Internet." Enough: improvement to computer functionality, particular machine, transformation of article to different state/thing.

⚠️ Impact on Practice:

Devastated business method and software patents. Claims must show technological improvement or solve technological problem, not just automate abstract idea on generic computer.

eBay Inc. v. MercExchange, L.L.C.
547 U.S. 388 (2006)
Remedies Injunctions

📜 Holding:

Permanent injunctions are not automatic upon finding infringement. Courts must apply traditional four-factor equity test. Rejected Federal Circuit's general rule that injunctions should issue absent exceptional circumstances.

eBay Four-Factor Test for Injunction:

  • Irreparable injury: Plaintiff suffered harm that cannot be remedied by money damages
  • Inadequate legal remedies: Money damages are insufficient to compensate plaintiff
  • Balance of hardships: Hardship to plaintiff if denied injunction outweighs hardship to defendant if granted
  • Public interest: Injunction would not disserve public interest

🎯 Exam Tips:

Injunctions are NOT automatic. Courts have discretion. Particularly impacts non-practicing entities (NPEs/trolls) who may not suffer irreparable harm since they don't make/sell products. Competitor is more likely to get injunction than NPE.

Mayo Collaborative Servs. v. Prometheus Labs., Inc.
566 U.S. 66 (2012)
§ 101 Eligibility Laws of Nature

📜 Holding:

Claims reciting natural correlation between drug metabolite levels and treatment efficacy are patent-ineligible. Merely instructing doctors to apply natural law (measure metabolite, adjust dosage) does not provide "significantly more" than law of nature itself.

Mayo Framework (basis for Alice):

  • Step 1: Determine if claim directed to law of nature, natural phenomenon, or abstract idea
  • Step 2: If yes, determine if additional elements transform claim into patent-eligible application
  • "Significantly more": Must be more than well-understood, routine, conventional activity
  • Cannot preempt: Claims cannot wholly preempt use of natural law/abstract idea

🎯 Exam Tips:

Diagnostic methods often fail Mayo test. "Administering, determining, wherein" claim format (administer drug, measure result, adjust based on correlation) typically ineligible unless transformation or technological improvement present.

Bilski v. Kappos
561 U.S. 593 (2010)
§ 101 Eligibility Business Methods

📜 Holding:

Machine-or-transformation test is important clue but not sole test for § 101 eligibility. Method of hedging risk in commodities trading is abstract idea and patent-ineligible. Business methods are not categorically excluded, but this claim was abstract.

🎯 Exam Tips:

Machine-or-transformation test: (1) Tied to particular machine, OR (2) Transforms article into different state/thing. This test is "important clue" but not exclusive test. Business methods can be patentable if not abstract.

Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co.
535 U.S. 722 (2002)
Doctrine of Equivalents Prosecution History Estoppel

📜 Holding:

Prosecution history estoppel arises when amendment narrows claim to overcome prior art or comply with § 112. Creates presumption that patentee surrendered all territory between original and amended claim. Presumption is rebuttable but strong.

🎯 Exam Tips:

Narrowing amendments create estoppel. Patent owner cannot later recapture surrendered scope through doctrine of equivalents. Can rebut by showing: (1) rationale bears no relation to equivalent, (2) couldn't reasonably describe equivalent, or (3) other reason amendment wasn't surrender.

🔷 Federal Circuit Cases (High-Yield)

Phillips v. AWH Corp.
415 F.3d 1303 (Fed. Cir. 2005) (en banc)
Claim Construction Intrinsic Evidence

📜 Holding:

Claims must be read in light of specification and prosecution history (intrinsic evidence). Specification is best guide to claim meaning. Dictionaries and extrinsic evidence are less reliable than intrinsic evidence.

Claim Construction Hierarchy:

  • 1. Claim language: Start with words of claim
  • 2. Specification: Single best guide to claim meaning
  • 3. Prosecution history: Shows how applicant/examiner understood claim
  • 4. Extrinsic evidence: Expert testimony, dictionaries (less weight)

🎯 Exam Tips:

For Patent Bar: Use broadest reasonable interpretation (BRI) during prosecution, not Phillips standard. Phillips applies in litigation. BRI means broadest meaning consistent with specification.

In re Wands
858 F.2d 731 (Fed. Cir. 1988)
§ 112(a) Enablement Undue Experimentation

📜 Holding:

Enablement requires disclosure sufficient for PHOSITA to make and use invention without undue experimentation. "Undue" is qualitative, not quantitative. Some experimentation is permitted.

Wands Factors for Undue Experimentation:

  • Breadth of claims
  • Nature of invention
  • State of prior art
  • Level of ordinary skill
  • Level of predictability in the art
  • Amount of direction/guidance in specification
  • Existence of working examples
  • Quantity of experimentation needed

🎯 Exam Tips:

Enablement is as of filing date. Specification must enable full scope of claims. If claims are broad (genus), enablement must cover entire genus, not just specific embodiments.

Ariad Pharms., Inc. v. Eli Lilly & Co.
598 F.3d 1336 (Fed. Cir. 2010) (en banc)
§ 112(a) Written Description

📜 Holding:

Written description is separate requirement from enablement. Must show possession of claimed invention as of filing date. Test: Would PHOSITA reading specification reasonably conclude applicant possessed claimed invention?

🎯 Exam Tips:

Written description vs. enablement: WD asks "did you have it?" Enablement asks "can others make it?" Original claims get presumption of WD support. New claims or amendments must have clear support in original disclosure.

In re Hyatt
211 F.3d 1367 (Fed. Cir. 2000)
Obviousness Burden of Proof

📜 Holding:

Examiner has initial burden to establish prima facie case of obviousness. If established, burden shifts to applicant to show nonobviousness (error in rejection, unexpected results, secondary considerations).

🎯 Exam Tips:

Prima facie case requires: (1) identify prior art teachings, (2) explain differences from claim, (3) articulate reasoning for why PHOSITA would combine teachings. Applicant can rebut with secondary considerations (commercial success, long-felt need).

In re Oetiker
977 F.2d 1443 (Fed. Cir. 1992)
§ 103 Obviousness Teaching Away

📜 Holding:

Prior art "teaches away" when it criticizes, discourages, or otherwise discourages the claimed solution. Mere disclosure of alternative does not teach away. Must actually discourage or lead away from claimed invention.

🎯 Exam Tips:

Teaching away is strong evidence of nonobviousness. But reference that merely shows alternative path (without discouraging claimed path) does NOT teach away. Must affirmatively discourage or criticize claimed approach.

In re Gleave
560 F.3d 1331 (Fed. Cir. 2009)
§ 102 Anticipation Inherency

📜 Holding:

Inherent anticipation requires that missing element is necessarily present in prior art, not that it may be or probably is present. Inherency cannot be established by probabilities or possibilities.

🎯 Exam Tips:

For inherency: element must be necessarily present, even if not recognized. If it's only sometimes present or probably present, NOT inherent. Natural result flowing from explicit disclosure can be inherent.

Therasense, Inc. v. Becton, Dickinson & Co.
649 F.3d 1276 (Fed. Cir. 2011) (en banc)
Inequitable Conduct Duty of Disclosure

📜 Holding:

Inequitable conduct requires but-for materiality (patent would not have issued but for misrepresentation/omission) AND specific intent to deceive. Both elements must be proven by clear and convincing evidence. Raised standard significantly.

🎯 Exam Tips:

Post-Therasense, inequitable conduct is harder to prove. Not enough to show "should have disclosed" - must show information was but-for material AND applicant specifically intended to deceive USPTO. High bar for both prongs.