Seeking to bypass a record-setting wave of procedural denials from the Patent Trial and Appeal Board (PTAB), which rose more than 630% year-over-year, defendants increasingly turned to the USPTO for ex parte reexaminations. In Q4 2025, the institution rate against NPEs fell to 33.6% (from 64.6% in Q1 2025) and against operating companies decreased to 53.2% (from 81.6%). This shift drove reexamination requests to an all-time high in 2025, representing a 66% increase over 2024 and signaling a major tactical pivot in patent validity challenges.
The surge in PTAB procedural denials and the record-high reexamination requests are the direct outcomes of procedural changes initiated by former Acting Director Coke Morgan Stewart (addressed in previous Unified Patents reports) and expanded by Director John Squires, who took office in September 2025, including most recently:
Revoking delegation of institution decisions from PTAB panels and assuming personal responsibility for all inter partes review (IPR) and post grant review (PGR) institution determinations. Under this new structure, the Director issues concise summary notices rather than detailed opinions; consultation with at least three PTAB judges is required, but final authority rests with the Director; and detailed treatment or referral to PTAB panels is reserved only for “novel or important” factual issues.
Restoring the practice of requiring PTAB petitioners to identify all real parties in interest before institution.
Although PTAB filings during the first six months of 2025 had been on pace to exceed previous levels—reaching 53.9% of the 2024 total—the year concluded with a downward trend. By year-end, total PTAB petitions had declined by 5.8% year-over-year.
The drop in PTAB institutions and petitions filed is likely to continue, given that in October 2025, the USPTO introduced proposed rules aimed at codifying the following restrictions for IPRs:
Petitioners must abandon all Section 102/103 defenses in all other forums in order to be eligible.
Denial is mandatory if any claim was previously upheld by the USPTO, ITC, or a court, regardless of the parties or prior art involved.
If a parallel proceeding is scheduled to resolve validity first, the petition must be denied.
The Director retains discretion to institute proceedings in "exceptional circumstances," though the proposed rules explicitly exclude new prior art, expert testimony, or case law developments from qualifying as exceptional.
Other key takeaways from 2025:
NPE district court filings jumped 21.6% in 2025 compared to 2024; overall, district court patent case filings increased by 12% over 2024’s numbers. The Eastern District of Texas remains the most popular court for patent case filings, including filings by NPEs.
Infringement actions filed in the Unified Patent Court (UPC) increased by 25% over 2024.
Procedural Denials in PTAB Increase Significantly: The PTAB issued a record-high 607 denials in 2025, and the number of pending PTAB petitions fell to a 10-year low.
PTAB Institution Rate Against NPEs Remains Below Operating Companies: Since the PTAB changed its procedures for discretionary denials earlier in 2025, the overall institution rate has dropped. In 2025, the institution rate for petitions against NPEs fell below the institution rate against operating companies. The institution rate is {the number of institutions during the 12-month sliding window period} ÷ {the total number of both institutions & denials during that same period}.
Quarterly Institution Rates in the PTAB by Entity: The quarterly PTAB institution rates decreased between Q1 and Q4 2025 for both NPEs and operating companies, with the institution rate against NPEs falling below 15% in Q3 before rebounding to just below 34% in Q4. The institution rate against operating companies was just below 34% in Q3 before increasing to 53.2% in Q4.
PTAB Procedural Denials vs. Requests for Ex Parte Reexaminations: Requests for ex parte reexaminations reached an all-time high (726) in 2025, mirroring the rise of discretionary denials at the PTAB, which also reached an all-time high (607) that same year.
Filings in 2025: PTAB petitions decreased 5.9% from 1,361 petitions in 2024 to 1,281 petitions in 2025. Requests for ex parte reexamination increased 66.1% from 437 requests filed in 2024 to 726 requests filed in 2025. District court patent cases increased 12% from 4,053 filings in 2024 to 4,531 filings in 2025.
The top five district courts for patent litigation filings in 2025: E.D.Tex. (27.7%), W.D.Tex. (11.5%), D.Del. (11.4%), N.D.Ill. (8.5%), and D.N.J. (5.0%). 2025 marks the apparent resurgence of the W.D.Tex., which in 2024 had been the fourth-most popular venue for patent litigation filings after the E.D.Tex., the N.D.Ill. and the D.Del.
The top five district courts for NPE patent litigation filings in 2025: Texas remains the epicenter of NPE litigation, with the E.D.Tex. (44.2%) and W.D.Tex. (17.5%) accounting for more than 60% of all cases. Other top venues included the D.Del. (8.7%), N.D.Tex. (3.8%), and N.D.Cal. (3.5%). Compared to 2024, the E.D.Tex. saw a slight decrease in its share, while the W.D.Tex. and D.Del. experienced modest growth.
Top 10 Plaintiffs in District Court in 2025: Nine of the top ten patent plaintiffs filing in district court in 2025 were NPEs, with the top spot going to Torus Ventures LLC, a Jeffrey Gross entity. In fact, three of the top district court patent plaintiffs in 2025 were Jeffrey Gross entities. Last year’s top patent plaintiff, Patent Armory, was the No. 3 patent plaintiff in 2025.
Post-Grant Proceedings in 2025: IPR petitions fell to 60.4% of total filings (from 73.0% in 2024), while ex parte reexaminations increased to 36.0% (up from 24.6%).
Top 10 Patent Owners in PTAB in 2025: Seven of the top ten patent owners defending against a PTAB petition filed in 2025 were NPEs.
Top 10 Defendants in District Court and Top 10 PTAB Petitioners in 2025: For both 2024 and 2025, Samsung ranked as the No. 1 defendant in district court patent filings and the No. 1 petitioner at the PTAB.
Filing Trends in District Court by Entity Type over Time: NPEs increased their lead in patent litigation, filing 55.4% of cases (up from 51.8% in 2024). Operating companies saw their share decrease to 41.2% (down from 44.9%).
Filing Trends in High Tech in District Court by Entity Type: In 2025, the concentration of NPE activity within the high-tech sector intensified. While NPEs accounted for 55.4% of all patent filings, they were responsible for a staggering 90.3% of high-tech patent litigation. This reflects a widening gap compared to 2024, when NPEs initiated 88% of high-tech cases despite comprising 51.8% of total patent filings.
Filing Trends in PTAB by Entity Type over Time: In a notable shift from 2024, NPEs became the primary targets of PTAB petitions in 2025. While operating companies owned the majority of challenged patents in 2024 (52.7%), they accounted for only 46.1% in 2025, with NPE ownership rising to 52.1%.
Filing Trends in High Tech at the PTAB by Entity Type: In 2025, NPEs were the target of 70.3% of high-tech PTAB challenges—an increase from 63.5% in 2024—yet they continued to drive a disproportionate 90.3% of high-tech district court litigation.
District Court Patent Litigation by Industry Type over Time: In 2025, high-tech litigation continued to dominate district court patent case filings, rising to 58.9% from 57% in 2024. Conversely, the share of medical-related cases saw a slight decline, falling from 13.3% in 2024 to 12.1% in 2025.
PTAB Petitions by Industry Type over Time: PTAB petitions in the high-tech industry rose to 73.1% (up from 69.6% in 2024), while medical-related petitions reached 12.7% (up from 11.6%).
Unified Patent Court: In 2025, the UPC saw a 25.6% increase in infringement actions (206 total) over 2024, peaking with an all-time monthly high in June. However, validity challenges cooled, with standalone revocations down 25.8% and counterclaims down 48.3%. NPE activity grew significantly, as their infringement actions as claimants increased by 50%. This boosted the NPE share of all infringement claimants to 21.8%, compared to 18.3% in 2024.
Definitions
Sectors
High-Tech = Technologies relating to Software, Hardware, and Networking
Medical = Technologies relating to Pharmaceuticals, Medical Devices, Health Related Technologies
Other = Technologies relating to Mechanical, Packaged Goods, Sporting Equipment and any other area outside of high-tech and medical patents.
Entities
Non Practicing Entity (NPE) = Company which derives the majority of its total revenue from Patent Licensing activities.
Operating Company or Op. Co. = Company which derives most of its total revenue from Product Sales or Services. Could be an SME or a large company.
Other Entity = Universities / Non-Profits / Government / Non-Governmental Organizations (NGOs)
NPE (Patent Assertion Entities) = Entity whose primary activity is licensing patents and acquired most of its patents from another entity
NPE (Small Company) = Entity whose original activity was providing products and services, but now is primarily focused on monetizing its own patent portfolio.
NPE (Individual) = Entity owned or controlled by an individual inventor who is primarily focused on monetizing inventions patents by that individual inventor.
NPE Aggregator = Entity that has control or ownership over two or more entities.
Litigation Investment Entities = Evidence of any third party with a financial interest, other than the assertors.
Venues
CACD = Central District of California
CAND = Northern District of California
DED = Delaware
Methodology
This report includes all District Court, PTAB, Reexam, and UPC cases between January 1, 2012 and December 31, 2025.
The total number of reported cases can vary based on what is included. Unified made its best attempt to eliminate mistaken, duplicative, or changes in venue filings, hence the totals may vary slightly compared to other reporting entities. Statistics include litigations initiated by NPEs or Declaratory Judgments (DJs) initiated by operating companies against NPEs.
Unified strives to accurately identify NPEs through all available means, such as court filings, public documents, and product documentation.