Prosecution Insights
Last updated: October 27, 2026

Nancy J Leith, USPTO Patent Examiner

Listed by the USPTO as LEITH, NANCY J

Tech Center 1600 • Art Units: 1600 1632 1636 1653 1656 1681 1683

This examiner grants 75% of resolved cases

Analysis

LEITH, NANCY J is assigned to Tech Center 1600 and Art Unit 1600. The profile records 834 resolved cases, a 74.7% allowance rate, and a 44.0% interview lift. The median time to allowance is 1105 days. The interview measure is a prominent feature of the record, showing a substantial reported association with allowance outcomes within a sizeable case base.

The listed companies are The Regents of the University of California, Flagship Pioneering Inc., and Editas Medicine Inc. The listed firms are FOLEY & LARDNER LLP, FISH & RICHARDSON P.C. (TC), and K&L Gates LLP - Tessera. Counsel may place significant emphasis on preparing for examiner interviews, including concise explanations of claim distinctions and proposed amendments. The allowance rate provides context for the overall prosecution environment, while the median duration should inform filing schedules and client expectations.

Written from this page's own data; every figure is computed from USPTO records and verified before publication.

Performance Statistics

74.7%
Allow Rate
+14.7% vs TC avg
896
Total Applications
+44.0%
Interview Lift
1105
Avg Prosecution Days
Based on 834 resolved cases, 2023–2026

Rejection Statute Breakdown

8.9%
§101 Eligibility
10.3%
§102 Novelty
29.2%
§103 Obviousness
29.3%
§112 Clarity

Currently Pending Office Actions

App #TitleStatusAssignee
17533007 EVALUATION OF CAS9 MOLECULE/GUIDE RNA MOLECULE COMPLEXES Non-Final OA EDITAS MEDICINE, INC.
17742127 NOVEL CRISPR ENZYMES AND SYSTEMS Non-Final OA MASSACHUSETTS INSTITUTE OF TECHNOLOGY
18171578 METHODS AND COMPOSITIONS FOR GENERATING A DELETION LIBRARY AND FOR IDENTIFYING A DEFECTIVE INTERFERING PARTICLE (DIP) Non-Final OA The Regents of the University of California
17763110 NOVEL RECEPTORS HAVING A HETEROLOGOUS STOP TRANSFER SEQUENCE FOR LIGAND-DEPENDENT TRANSCRIPTIONAL REGULATION Non-Final OA The Regents of the University of California
19272711 METHODS AND COMPOSITIONS FOR MODULATING A GENOME Final Rejection Flagship Pioneering Innovations VI, LLC
19272775 METHODS AND COMPOSITIONS FOR MODULATING A GENOME Final Rejection Flagship Pioneering Innovations VI, LLC
17608429 MULTIPARTITE CRISPR DONOR Non-Final OA DSM IP Assets B.V.
17201347 DELIVERY, USE AND THERAPEUTIC APPLICATIONS OF THE CRISPR-CAS SYSTEMS AND COMPOSITIONS FOR TARGETING DISORDERS AND DISEASES USING VIRAL COMPONENTS Non-Final OA President and Fellows of Harvard College
17309426 METHODS FOR EX VIVO EXPANSION OF NATURAL KILLER CELLS AND USE THEREOF Non-Final OA Board of Regents, The University of Texas System
19174171 ENGINEERED CIRCULARIZED pegRNAs AND USES THEREOF Final Rejection Trustees of Boston University
17832457 METHODS AND COMPOSITIONS FOR RNA-GUIDED TREATMENT OF HIV INFECTION Final Rejection Temple University-of The Commonwealth System of Higher Education
17503928 CRISPR-CAS COMPONENT SYSTEMS, METHODS AND COMPOSITIONS FOR SEQUENCE MANIPULATION Non-Final OA The Rockefeller University
18107108 COMPOSITIONS AND METHODS OF USE OF CRISPR-CAS SYSTEMS IN NUCLEOTIDE REPEAT DISORDERS Non-Final OA University of Iowa Research Foundation
18269046 MDH GENE-BASED POLYNUCLEOTIDE HAVING PROMOTER ACTIVITY AND USE THEREOF Non-Final OA TIANJIN INSTITUTE OF INDUSTRIAL BIOTECHNOLOGY, CHINESE ACADEMY OF SCIENCES

Facing This Examiner?

IP Author analyzes examiner patterns and generates tailored response strategies with the highest chance of allowance.

Build Your Strategy

Who Appears Before This Examiner

Top companies before this examiner

Law firms appearing most often

Frequently Asked Questions

What is examiner Nancy J Leith's allowance rate?

74.7% of resolved applications examined by Nancy J Leith were allowed (834 resolved cases), compared with 37.3% across Art Unit 1600 over the last five years.

Does an interview help with examiner Nancy J Leith?

This examiner's interview lift is +44.0 percentage points: the difference in allowance rate between resolved applications that had an examiner interview and those that did not.

How long does examiner Nancy J Leith take to allow a patent?

Applications allowed by Nancy J Leith took 1,105 days on average from filing to allowance.

Which art unit does examiner Nancy J Leith work in?

Nancy J Leith examines applications in Art Unit 1600 in Tech Center 1600 (Biotechnology & Pharmaceuticals).

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month