Prior Art

Prior art is any evidence that an invention was already publicly known before the patent application's effective filing date: AIA § 102(a)(1) — ABSOLUTE PRIOR ART: a claimed invention lacks novelty if it was 'patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention'; TYPES OF PRIOR ART: (a) PATENTS AND PATENT APPLICATIONS: US patents; US published applications (published 18 months after earliest priority date); foreign patents; PCT published applications; these are the most commonly cited type of prior art; (b) PRINTED PUBLICATIONS: journal articles; conference papers; preprints (arXiv, bioRxiv); textbooks; technical manuals; product brochures; website content (if publicly accessible on a specific date); theses and dissertations; (c) PUBLIC USE: use of the invention in public (even without sales); demonstration at a trade show; use in a factory visible to visitors; use in a public place; (d) ON SALE: offer to sell the invention for commercial purposes; an offer to sell starts the on-sale bar even without a completed sale; Pfaff v. Wells Electronics (S.Ct. 1998): the invention must be (1) the subject of a commercial offer for sale; and (2) ready for patenting; (e) OTHERWISE AVAILABLE TO THE PUBLIC: catch-all added by AIA; covers new forms of disclosure not listed; social media posts; YouTube videos; online product listings; public demonstrations; GEOGRAPHIC SCOPE (AIA): prior art can be from anywhere in the world (not just the US as under pre-AIA § 102(a)); AIA § 102(a)(2) — SECRET PRIOR ART: an earlier-filed US patent application that published later is prior art from its filing date (even before publication).

The AIA substantially changed what constitutes prior art in important ways: PRE-AIA § 102 PRIOR ART CATEGORIES: § 102(a): known or used by others IN THE UNITED STATES; or patented or described in a printed publication ANYWHERE before the date of invention; note: 'known or used' required US geographic scope; § 102(b): patented, described in a printed publication, in public use, or on sale IN THIS COUNTRY more than one year before the filing date; this created the 12-month GRACE PERIOD for EVERYONE (not just inventors); § 102(e): description in a US patent granted on an application filed before the applicant's date of invention; § 102(g): made in the US before the applicant's date of invention (first-to-invent); AIA § 102 CHANGES: AIA § 102(a)(1): geographic limitation removed; prior art includes anything anywhere 'available to the public'; AIA replaces the pre-AIA 12-month grace period for third-party disclosures with NO grace period for third-party disclosures; ONLY the inventor's own disclosures within 12 months get the grace period; AIA § 102(a)(2): prior art from earlier-filed US or PCT applications from their filing date (not just from publication); § 102(g) first-to-invent prior art: ELIMINATED; first-to-invent cannot overcome prior art under AIA; KEY PRACTICAL DIFFERENCES: pre-AIA: a publication published AFTER the date of invention was NOT prior art under § 102(a) if the inventor could prove earlier invention date ('swearing behind'); AIA: any publication before the effective filing date IS prior art, no swearing behind possible; pre-AIA: a third party's public use or sale in the US within 1 year of filing was prior art (§ 102(b) grace period for all); AIA: a third party's public use before filing date IS immediately prior art (no grace period for third parties).

Prior art is the primary basis for challenging patent claims both in prosecution and litigation: § 102 ANTICIPATION: a prior art reference anticipates a claim if it discloses EVERY ELEMENT of the claim (all-elements rule); the reference must disclose each element explicitly or inherently; no combination of references for § 102 (single reference must contain everything); inherent disclosure: a prior art process that necessarily produces a particular result discloses that result even if not described; § 103 OBVIOUSNESS: even if no single reference anticipates, a claim may be obvious if a combination of prior art references renders it obvious; Graham v. John Deere (S.Ct. 1966): scope and content of prior art; differences between prior art and claim; level of ordinary skill in the art; secondary considerations (objective indicia of non-obviousness); KSR International v. Teleflex (S.Ct. 2007): flexible approach; no rigid TSM test required; 'obvious to try' can establish obviousness when a finite number of identified, predictable solutions exist; EXAMINER USE: examiners search multiple databases (USPTO patent database; European Patent Register; JPO; non-patent literature databases) to find prior art; the examiner bears the burden of making a prima facie case of unpatentability; LITIGATION USE: validity is presumed (35 U.S.C. § 282); defendant must show invalidity by clear and convincing evidence; Microsoft v. i4i (S.Ct. 2011): clear and convincing evidence standard applies even to prior art not considered by the examiner; INTER PARTES REVIEW (IPR): preponderance of the evidence standard; only patents and published applications can be used; faster and cheaper than litigation; 68% of challenged claims are cancelled or amended (2023 statistics); POST-GRANT REVIEW (PGR): any ground of invalidity; must be filed within 9 months of grant.

The AIA grace period protects inventors' own disclosures made within 12 months of filing: AIA § 102(b)(1) GRACE PERIOD: a disclosure is NOT prior art against a claimed invention if: EXCEPTION A: the disclosure was made by the inventor (or joint inventor) within 1 year before the effective filing date; EXCEPTION B: the disclosure was made by another person who obtained the subject matter from the inventor, within 1 year before the effective filing date; WHAT THE GRACE PERIOD PROTECTS: inventor publishes an article in a journal; the article is prior art under § 102(a)(1); but under § 102(b)(1)(A), the article is REMOVED from prior art if filed within 12 months of the article's publication date; WHAT THE GRACE PERIOD DOES NOT PROTECT: third-party disclosures that do NOT originate from the inventor; if competitor independently discovers and publishes the same invention before your filing date, that publication IS prior art with no grace period exception; PRE-AIA DIFFERENCE: under pre-AIA § 102(b), any disclosure (by anyone) more than 1 year before filing creates a statutory bar; disclosures within 1 year of filing (by ANYONE) were generally outside the statutory bar; AIA is NARROWER for third-party disclosures (no grace period for third parties), but SAME for inventor's own disclosures (12-month grace); DERIVED DISCLOSURE EXCEPTION: if a third party's disclosure derived from the inventor's earlier disclosure, the third-party disclosure is also removed from prior art; protects against scenario: inventor publishes → third party reads publication → third party publishes similar article → inventor's patent application; the third-party article doesn't become prior art because it derived from the inventor; FOREIGN RIGHTS WARNING: the 12-month grace period for the inventor's own disclosures does NOT help with foreign patent rights; most countries have absolute novelty requirements (any public disclosure before filing = loss of patent rights); file BEFORE any public disclosure to preserve foreign rights.

A thorough prior art search requires multiple databases and search strategies: WHY SEARCH PRIOR ART: before filing: assess patentability; refine claim scope; avoid wasting money on unpatentable inventions; during prosecution: anticipate examiner rejections; prepare arguments and amendments; freedom to operate: confirm you can practice the invention without infringing others' patents; pre-litigation: assess strength of claims; find invalidity arguments; PATENT DATABASES: USPTO Patent Full-Text Database (patents.google.com): all US patents and published applications; full text search; Google Patents (patents.google.com): US + international; machine translation; forward/backward citation analysis; WIPO PatentScope: PCT applications + national patent databases; Espacenet (European Patent Office): 120M+ documents; global coverage; Derwent Innovation (commercial): advanced analytics; patent family tracking; chemical structure search; CAS SciFinder (pharma/chem): chemical compound and reaction databases; NON-PATENT LITERATURE (NPL): critical for science-intensive patents (pharma, biotech, materials science); PubMed: biomedical literature; IEEE Xplore: electrical engineering and computer science; Web of Science: broad science; Google Scholar: free broad search; conference proceedings (often not indexed in major databases — manual search required); CLASSIFICATION SEARCH: IPC (International Patent Classification): international; hierarchical; CPC (Cooperative Patent Classification): joint USPTO/EPO system; more granular than IPC; searching by classification finds patents even without keyword matches; SEARCH STRATEGY: keyword search + classification search + citation search (backward from known references + forward from known references); iteratively expand based on findings; PROFESSIONAL SEARCHES: patent agents and professional searchers use multiple databases; US patent search typically takes 3-8 hours; full patentability opinion: $1,500-$5,000.