Patent Law Deep Dive — Prosecution Procedure, Post-Grant Proceedings, and Infringement Analysis

The Structure of US Patent Law

US patent law is designed to balance two competing interests: rewarding inventors with a limited monopoly and advancing the public interest through disclosure of new technology. The Patent Bar Exam tests your command of every major aspect of this system.

Core patent rights:

Right to exclude: The patent owner can exclude others from making, using, selling, offering for sale, or importing the patented invention (35 U.S.C. § 271)
Duration: 20 years from the earliest effective filing date (utility and plant patents); 15 years from grant (design patents)
Nature of right: A right to exclude, not a right to practice (you may still be blocked by a dominant patent)

Patent Prosecution Timeline

Full Prosecution Flow

Invention Disclosure
  ↓
Provisional Application (optional; establishes priority date; 12 months to convert)
  ↓
Non-Provisional Application Filing (sets the effective filing date)
  ↓
Application Publication (18 months from earliest priority date; unless non-publication request)
  ↓
Request for Examination (included in filing fee; automatic for most applications)
  ↓
Office Action (Examiner issues rejection or objection; typically 6-month shortened stat. period)
  ↓
Applicant Response (arguments, claim amendments; can request extension of time)
  ↓
Final Office Action (further rejections after response) or Notice of Allowance
  ↓
After Final: RCE, appeal to PTAB, or continuation application
  ↓
Issue Fee Payment → Patent Grant
  ↓
Maintenance Fees (3.5 / 7.5 / 11.5 years after grant)

First-Inventor-to-File (AIA, Effective March 16, 2013)

Under the America Invents Act, priority goes to the first inventor to file a patent application, not the first to conceive or reduce the invention to practice. This aligns US practice with the rest of the world.

Key AIA grace period: An inventor’s own disclosure within 12 months before the effective filing date does not constitute prior art against the inventor’s own application (35 U.S.C. § 102(b)(1)(A)).

Patentability Requirements

Subject-Matter Eligibility (§ 101)

The invention must fall into a statutory category (process, machine, manufacture, or composition of matter) and must not be directed solely to a judicial exception.

Judicial exceptions: Abstract ideas, laws of nature, natural phenomena. The two-step Alice/Mayo framework applies:

Step 1: Is the claim directed to a judicial exception?
Step 2: Do the additional claim elements amount to significantly more than the exception itself?

Novelty (§ 102)

Prior art under AIA § 102: A claimed invention lacks novelty if it was patented, described in a printed publication, in public use, on sale, or otherwise available to the public before the effective filing date.

Anticipation: Prior art anticipates a claim if a single prior art reference discloses every element of the claim.

Non-Obviousness (§ 103)

Graham v. John Deere framework (Supreme Court, 1966):

Scope and content of the prior art
Differences between the prior art and the claimed invention
Level of ordinary skill in the pertinent art (PHOSITA)
Secondary considerations (commercial success, long-felt unmet need, failure of others, copying by competitors)

Enablement and Written Description (§ 112)

Enablement: The specification must enable a PHOSITA to make and use the full scope of the claimed invention without undue experimentation.

Written description: The specification must demonstrate that the inventor possessed the claimed invention at the time of filing. Relevant in continuation and divisional practice, and frequently at issue in biotech/pharma cases.

Post-Grant Proceedings

Five Types of PTAB Proceedings

Proceeding	Who Files	Grounds	Key Timing
Inter Partes Review (IPR)	Any person / entity	§ 102, § 103 (patents & publications only)	Within 1 year of service of infringement complaint
Post-Grant Review (PGR)	Any person / entity	Any ground of invalidity	Within 9 months of patent grant
Ex Parte Reexamination	Patent owner or third party	§ 102, § 103	Any time during patent life
Covered Business Method (CBM) Review	Persons sued for infringement	Any ground; financial products focus	Sunset provision; largely expired
Supplemental Examination	Patent owner only	Any information; prevents inequitable conduct	Any time during patent life

Appeals from PTAB

PTAB decisions in IPR/PGR proceedings are appealed to the U.S. Court of Appeals for the Federal Circuit (CAFC). CAFC decisions can be reviewed by the Supreme Court on certiorari. For ex parte appeals from prosecution, the applicant may also appeal to the U.S. District Court for the Eastern District of Virginia.

Patent Infringement Analysis

Literal Infringement

A product or process literally infringes a patent claim if it includes every element of the claim as written. Use the all-elements rule: a claim is not literally infringed if even one element is absent from the accused product or process.

Doctrine of Equivalents (DoE)

Infringement may still occur even without literal infringement if the accused product or process performs substantially the same function, in substantially the same way, to achieve substantially the same result as the claimed invention (Function-Way-Result test, Graver Tank).

Prosecution history estoppel limits the scope of DoE: if the applicant narrowed a claim during prosecution to overcome prior art, the surrendered subject matter cannot later be recaptured through DoE.

Indirect Infringement

Induced infringement (§ 271(b)): Actively inducing another party to directly infringe. Requires knowledge of the patent and specific intent to cause infringement.

Contributory infringement (§ 271(c)): Selling a component with no substantial non-infringing use, knowing it will be used to infringe. Requires knowledge of the patent.

Patent Infringement Remedies

Remedy	Description
Injunction (§ 283)	Permanent or preliminary; bars continued infringement; governed by eBay four-factor test
Damages (§ 284)	Minimum: reasonable royalty; preferred: lost profits (Panduit factors); enhanced damages for willful infringement (up to 3×)
Attorney’s Fees (§ 285)	In “exceptional cases” (willful infringement, litigation misconduct)
Seizure / ITC Action	US International Trade Commission Section 337 investigations for import exclusion
Criminal Penalties	For patent fraud / inequitable conduct (rare; civil remedy is unenforceability)

Study Checklist

Can walk through the full prosecution timeline from provisional to maintenance fees
Can state the AIA grace period rule and the first-inventor-to-file standard
Can apply the § 101 Alice/Mayo two-step analysis to a software or business method claim
Can apply the Graham v. John Deere four-factor framework to an obviousness question
Can compare IPR, PGR, and ex parte reexamination on timing, standing, and available grounds
Can explain the distinction between literal infringement and the doctrine of equivalents
Can identify when prosecution history estoppel bars a DoE argument
Can list the available remedies for patent infringement and the standard for each

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