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AI, semiconductors & telecommunications / 2006–2020

A semiconductor engineer used U.S. filter secrets to build a university-backed competitor in China S1 S2

A bench trial found that Hao Zhang and collaborators moved radio-frequency filter know-how from Avago and Skyworks into a Tianjin University-linked manufacturing venture. S1 S2

Evidence at a glance How labels work

Evidence status Adjudicated
Case-level nexus context Court-established or admitted
Public sources 3 Automated checks verify citation linkage; editorial review judges support
Evidence foundation Official summaries only The adjudicated outcome is currently linked through official government summaries; no dispositive court document is yet included. S1 S2
Publication record Published Aug 23, 2026 Reviewed Aug 25, 2026 · Next Aug 23, 2027

Evidence status and PRC-state nexus answer different questions and must not be joined across different actors. Actor-specific outcomes appear below.

Compare this file
Finding

A federal judge convicted Hao Zhang of economic espionage, trade-secret theft, and related conspiracies after finding that he intended to build a competing business with stolen technology and knew the venture would benefit PRC instrumentalities, including Tianjin University. S1 S2

01 / Executive brief

Executive summary

Hao Zhang worked at Skyworks while a collaborator worked at Avago, placing the pair on opposite sides of the specialized radio-frequency filter market. Instead of treating their employers' surface- and bulk-acoustic-wave processes as separate confidential portfolios, the collaborators shared protected know-how and used the combined package to plan a competing manufacturing business in China. S1 S2

The commercialization route ran through Tianjin University appointments, Chinese patent applications, an offshore entity, a university subsidiary, and a manufacturing venture called ROFS. After a bench trial, a federal judge convicted Zhang of economic espionage, trade-secret theft, and conspiracy, ordered $476,835 in restitution, and required forfeiture of patents derived from stolen Avago technology. S1 S2

Small surface acoustic wave radio-frequency filter component photographed beside a ruler
technology

Surface-acoustic-wave filters are compact components that separate radio bands inside communications equipment. The case concerned protected filter designs and manufacturing processes. Contextual image; not a component made by the parties.

Mister rf · CC BY-SA 4.0 ↗

02 / The vignette

What happened

Two employers supplied complementary secrets

Mobile devices rely on tiny acoustic filters to isolate desired radio bands. Zhang's Skyworks role and Wei Pang's Avago role exposed them to different confidential designs, processes, and manufacturing methods. Trial evidence showed that those employer boundaries were crossed as secrets moved among collaborators developing a single competing plan. S1 S2

Academic appointments became industrial infrastructure

In 2009, Zhang and Pang obtained Tianjin University professorships tied to creating a micro-electromechanical-systems laboratory. The group pursued Chinese patent applications and organized corporate entities; a Tianjin University subsidiary and an offshore collaborator entity then formed ROFS to manufacture products realized from the acquired technology. S1 S2

The court connected theft to state benefit

Zhang was arrested after arriving in Los Angeles in 2015. Following a four-day bench trial, the court found that he stole Avago and Skyworks trade secrets, intended to build a competing China-based business, and knew it would benefit PRC instrumentalities including Tianjin University. He received 18 months in prison, restitution, supervised release, and forfeiture of patents obtained with stolen Avago technology. S1 S2

03 / Anatomy

How access became transfer

This six-part framework asks the same questions of every file. Each stage carries its own evidence state; a listed stage can be alleged, inferred, interrupted, disputed, or not established. The structure does not manufacture a completed transfer or harm.

  1. 01

    Relationship context Documented

    Specialist engineering roles

    Zhang worked at Skyworks while Pang worked at Avago, placing both inside firms developing advanced mobile-device filters. S1 S2

  2. 02

    Access assessed Documented

    Complementary filter know-how

    Their jobs exposed them to confidential surface- and bulk-acoustic-wave designs, processes, and manufacturing information. S1 S2

  3. 03

    Acquisition assessed Adjudicated or admitted

    Secrets shared across employers

    Trial evidence showed Zhang and Pang illicitly shared employer trade secrets with one another and with collaborators in China. S1

  4. 04

    Movement assessed Documented

    University and patent pathway

    They obtained Tianjin University professorships, pursued Chinese patent applications, and organized entities to carry the technology into a China-based venture. S1 S2

  5. 05

    Downstream use assessed Adjudicated or admitted

    Manufacturing venture created

    A Tianjin University subsidiary and the collaborators' offshore entity formed ROFS to manufacture products realized from the trade secrets. S1

  6. 06

    Consequences assessed Adjudicated or admitted

    Economic espionage proved

    The court convicted Zhang and ordered imprisonment, restitution, supervised release, and forfeiture of U.S. patents derived from stolen Avago technology. S1

04 / Evidence boundary

What is established—and what is not

Established in the record

  • The trial court found that Zhang stole Avago and Skyworks filter trade secrets and intended to use them in a new China-based business. S1
  • The court found that Zhang knew the venture would benefit PRC instrumentalities, including Tianjin University. S1
  • The commercialization structure joined university appointments, patent filings, an offshore entity, a university subsidiary, and a manufacturing venture. S1 S2

Uncertain, limited, or unresolved

  • The 2015 announcement charged six people, but this file treats only Zhang's later conviction as adjudicated and does not assign his outcome to the other defendants. S1 S2

Subject response / procedural context

  • Zhang contested the case at a bench trial. The judge found him guilty; this file does not treat the original allegations against other defendants as proven by Zhang's judgment. S1 S2

05 / Sequence

Timeline

  1. Parallel employment begins

    Zhang joined Skyworks, Pang joined Avago, and the collaborators began formulating a China-based competing business. S1

  2. University appointments

    Zhang and Pang obtained Tianjin University professorships tied to creating a micro-electromechanical-systems laboratory. S1

  3. Zhang arrested

    Federal agents arrested Zhang after he arrived in Los Angeles; the Justice Department announced the charges three days later. S2 S3

  4. Sentence imposed

    Following his bench-trial conviction, Zhang received 18 months in prison and was ordered to pay $476,835 in restitution. S1

06 / People and institutions

Who appears in the public record

Hao Zhang

Former Skyworks engineer, Tianjin University professor, and venture participant S1 S2 S3

Outcome: Convicted at trial and sentenced to 18 months, restitution, supervised release, and patent forfeiture S1 S2

Actor-specific PRC nexus Court-established or admitted

Hao Zhang: The trial judge found that Zhang knew the China-based business would benefit PRC instrumentalities, including Tianjin University. That adjudicated finding applies to Zhang's conduct; it should not be generalized to every person or institution named in the original indictment. S1 S2

Wei Pang

Former Avago engineer and alleged co-conspirator named in the charging record S1 S2

Outcome: Not adjudicated in the sources cited here S1 S2

Actor-specific PRC nexus Unknown / insufficient public evidence

Pang was named in the charging record, but the sources reviewed here do not separately adjudicate his conduct or assign him a proven PRC-state relationship. S1 S2

Tianjin University

PRC university found by the trial court to be an instrumentality expected to benefit from the venture S1 S2

Actor-specific PRC nexus Court-established or admitted

Tianjin University: The trial judge found that Zhang knew the China-based business would benefit PRC instrumentalities, including Tianjin University. That adjudicated finding applies to Zhang's conduct; it should not be generalized to every person or institution named in the original indictment. S1 S2

ROFS Microsystems

Joint venture formed to manufacture products using the transferred filter technology S1 S2

Actor-specific PRC nexus Documented affiliation or support

ROFS was formed with Tianjin University participation, but the cited record does not separately adjudicate ROFS as a convicted actor. S1 S2

Originator / affected institution

Avago Technologies

Developer and owner of protected FBAR and related filter technology S1 S2

Originator / affected institution

Skyworks Solutions

Developer and owner of protected radio-frequency filter technology S1 S2

07 / Consequences

Documented, attributed, potential, and unknown consequences

Court finding

The sentencing court ordered $476,835 in restitution to Avago and Skyworks and forfeiture of patents obtained with stolen Avago technology. S1

Documented record

The trade secrets supported a manufacturing venture positioned to compete in radio-frequency components used in consumer and military applications. S1

08 / Hindsight analysis

Where leadership could have seen risk

These are our analytic judgments based on the public record, not court findings. They are framed to improve controls without treating nationality as a risk factor.

Complementary insiders bridged silos

Employees at two competing firms could combine protected knowledge into a fuller manufacturing package than either person held alone.

Appointments became a transfer channel

University roles, patents, offshore entities, and a joint venture converted insider knowledge into an organized commercialization pathway.

Patent activity surfaced too late

Related patent filings can reveal protected technical claims, but only if employers monitor inventor and affiliate activity through a lawful review process.

09 / Apply the lesson

Actions leaders can take

  1. companies

    Model collusive insider risk

    Look for coordinated access, communications, and departures across employees who hold complementary portions of a crown-jewel process, subject to legal and privacy controls.

  2. both

    Reconcile appointments and patents

    Compare disclosed outside appointments, company formation, and inventor activity with confidentiality, invention-assignment, and sponsored-research obligations.

  3. companies

    Protect process combinations

    Map the set of recipes, tolerances, tooling, and troubleshooting knowledge needed to reproduce a product—not just individual files—and segment access accordingly.

10 / Source record

Sources

Links point to the public record reviewed for this file. Government releases can summarize court proceedings but remain government-authored sources; the source note identifies those limits.

  1. S1

    Chinese Citizen Sentenced for Economic Espionage, Theft of Trade Secrets, and Conspiracy ↗

    U.S. Attorney's Office for the Northern District of California · Published Sep 1, 2020 · Retrieved Aug 23, 2026

    Sentencing and bench-trial findings, including the beneficiary, commercialization path, restitution, and forfeiture.

    official summary government release
  2. S2

    Chinese Professors Among Six Defendants Charged with Economic Espionage and Theft of Trade Secrets ↗

    U.S. Department of Justice · Published May 19, 2015 · Retrieved Aug 23, 2026

    Charging-stage chronology and entity structure; allegations against people other than Zhang are not treated as adjudicated.

    official summary government release
  3. S3

    United States v. Hao Zhang, Order Denying Motion to Suppress Post-Arrest Statements ↗

    U.S. District Court for the Northern District of California via GovInfo · Published Feb 9, 2018 · Retrieved Aug 25, 2026

    Locator: United States v. Zhang, No. 5:15-cr-00106, ECF No. 199

    Primary procedural order concerning Zhang's post-arrest statements and charging background; it predates trial and does not establish the later conviction.

    procedural record court record

12 / Reference

Cite this dossier

Use the permanent URL and review date below so readers can identify the version of the public-source record you consulted.

ChinaSteals. “A semiconductor engineer used U.S. filter secrets to build a university-backed competitor in China.” CS-007. Published Aug 23, 2026; last reviewed Aug 25, 2026. https://chinasteals.com/cases/hao-zhang-rf-filters/

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