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primarysourced Photonics sector Tower
TSEM
~15 min read · 3,375 words ·updated 2026-04-29 · ◐ partial · confidence 36%

Customer-side primary-source verification — 2026-04-29

This file records the outcome of a focused EDGAR full-text-search and per-CIK 10-K / 20-F sweep designed to promote, partially promote, or reject the aggregator-only customer-name attributions in Customers — diversified. Tower’s own 20-F names exactly one customer (NTCJ, 13% of FY 2024 revenue); every other named customer has historically rested on aggregator framing or Tower’s own historical press releases. Where the customer’s own SEC filing names Tower / TowerJazz / Jazz Semiconductor / Newport Fab as a foundry partner, the attribution is promoted to ✓ verified-primary with the customer-side filing as the citation.

Scope: SEC EDGAR full-text search (efts.sec.gov), per-CIK submissions JSON, direct retrieval of each candidate’s most recent 10-K / 20-F HTML, full-text scan for the trigger phrases. Headers paraphrased; one-sentence verbatim quotes only where load-bearing.

Summary table

Customer (ticker)New confidenceBasisCitation (customer filing)
Vishay (VSH) — Siliconix subsidiary✓ verified-primaryFY 2022 10-K names Tower Semiconductor as long-term foundry partner since 2004; multi-year minimum purchase commitmentsVSH FY 2022 10-K (filed 2023-02-22)
Maxim Integrated (now part of ADI)✓ verified-primary (historical, succeeded by ADI)FY 2021 10-K names long-term wafer supply agreement with TowerJazz Texas Inc. (San Antonio Fab 9) executed 2015-11-18MXIM FY 2021 10-K (filed 2021-08-20)
Impinj (PI)✓ verified-primaryFY 2021 10-K explicitly states Tower is sole reader-IC wafer supplier since 2008 (genericized to “foundry partners” in FY 2023+; no public severance disclosure)Impinj FY 2021 10-K (filed 2022-02-14)
Inphi (now Marvell MRVL)✓ verified-primary (historical, succeeded by Marvell)FY 2019 10-K names TowerJazz as one of four principal foundries (with TSMC, WIN Semiconductors, GlobalFoundries)Inphi FY 2019 10-K (filed 2020-03-02)
O2Micro (OIIM)✓ verified-primaryFY 2021 20-F names TowerJazz Panasonic Semiconductor (TPSCo, Tower subsidiary) among three top foundries that manufactured “most” of O2Micro’s IC volume in 2021O2Micro FY 2021 20-F (filed 2022-04-18)
Skyworks Solutions (SWKS)◐ partial — Tower-side primary, no recent customer-side filingTower’s 2012 IR press release names Skyworks Foundry Supplier of the Year; SWKS FY 2025 10-K silent on specific foundry partners; older Skyworks 10-Ks reference Jazz Semiconductor only as Conexant-merger warrant counterparty (not foundry)Tower IR release 2012 (Tower-side); SWKS FY 2025 10-K (silent)
Analog Devices (ADI)◐ partial — supply agreement inherited from Maxim, not separately named in ADI 10-KMaxim FY 2021 10-K named TowerJazz Texas Inc. supply agreement (Nov 18 2015); Maxim acquired by ADI Aug 2021; ADI FY 2025 10-K does not separately disclose Tower (likely below materiality threshold post-merger)MXIM FY 2021 10-K (Maxim-as-predecessor); ADI FY 2025 10-K (silent)
Qorvo (QRVO)⚠ aggregator-only (negative customer-side check)FY 2025 10-K silent on Tower / TowerJazz / Jazz / Newport / TSMC / GlobalFoundries — no specific foundry partner namedQRVO FY 2025 10-K (filed 2025-05-19)
Broadcom (AVGO)⚠ aggregator-only (negative customer-side check)FY 2025 10-K names TSMC (6 hits) but no Tower / TowerJazz / Jazz / Newport referenceAVGO FY 2025 10-K (filed 2025-12-18)
Semtech (SMTC)⚠ aggregator-only (silent)FY 2026 10-K (filed 2026-03-23) silent on all trigger phrases; no specific foundry namedSMTC FY 2026 10-K
Texas Instruments (TXN)⚠ aggregator-only (silent — likely internal-fab)FY 2025 10-K silent on Tower / TowerJazz / Jazz / Newport; TI is largely internal-fabTXN FY 2025 10-K (filed 2026-02-06)
ON Semiconductor (ON)⚠ aggregator-only (silent — likely internal-fab)FY 2025 10-K silent on all trigger phrases; ON is largely internal-fabON FY 2025 10-K (filed 2026-02-09)
Lattice Semiconductor (LSCC)✗ excludedFY 2025 10-K explicitly names UMC, USJC, Samsung, TSMC, Epson as foundry partners — Tower NOT in the listLSCC FY 2025 10-K (filed 2026-02-13)
Cirrus Logic (CRUS)✗ excludedFY 2025 10-K names TSMC; no Tower / TowerJazz / Jazz / Newport referenceCRUS FY 2025 10-K (filed 2025-05-23)
Renesas Electronics (6723.T)✗ excluded (publicly-named GFS partnership)Renesas’s publicly-disclosed foundry alliance is with GlobalFoundries (expanded Feb 2025; tape-outs mid-2026); Renesas does not file 10-K but does not disclose Tower in English-language IR materials(no SEC filing; trade-press cited at Mark Lapedus on the Foundry Ecosystem (Substack))
NXP Semiconductors (NXPI)⚠ aggregator-only (silent)FY 2024 10-K does not contain “Tower Semiconductor” or “TowerJazz” (EDGAR full-text search returns 0 hits for NXPI CIK 0001413447)NXPI 10-K filings index
Murata Manufacturing⚠ aggregator-only (no SEC filing)Murata is Japanese-listed (no 10-K / 20-F); web search returns no Tower-Murata foundry-relationship primary disclosure(no primary source located)
Samsung Semiconductor (Samsung Electronics)⚠ aggregator-only (no SEC filing)Samsung Electronics is Korea-listed; primarily internal-fab; no Tower-Samsung foundry primary disclosure located(no primary source located)
Infineon Technologies (IFX.DE)⚠ aggregator-only (no SEC filing)German-listed; primarily internal-fab; no Tower-Infineon foundry primary disclosure located(no primary source located)
Teledyne Technologies (TDY)⚠ aggregator-only (silent)EDGAR full-text search of TDY 10-Ks for “Tower Semiconductor” returns 0 hits; no customer-side disclosure of Tower as a foundry(no primary source located)

A. Skyworks Solutions (SWKS) — ◐ partial

EDGAR search result: SWKS CIK 0000004127 has 6 historical 10-K hits for “Jazz Semiconductor” (2002-2006), but each hit refers to a stock-warrant agreement issued at the June 2002 Conexant-Alpha-Industries merger that formed Skyworks (Conexant spun out its wireless business; Jazz was the sister foundry-business spun off in parallel). The warrant is a financial-instrument legacy, not a foundry-supply attestation.

Most recent 10-K (FY 2025, filed 2025-11-07, accession 0000004127-25-000085, primary doc swks-20251003.htm): silent on Tower / TowerJazz / Jazz / Newport / TSMC. The Operations / Risk Factors language describes “long-term supply arrangements” with “third-party foundries” generically without naming any one foundry.

Tower-side evidence: Tower’s own 2012 IR press release naming Skyworks Foundry Supplier of the Year (TowerJazz era) is the cleanest primary attestation and remains valid per customers diversified Section 3.1.

Verdict: ◐ partial. Tower-side primary source is solid (2012); customer-side (SWKS) modern 10-Ks have generic language and do not name Tower. The relationship’s current 2026 status (volume, share, post-Skyworks-Qorvo-merger trajectory) is therefore not customer-side primary verified.

B. Qorvo (QRVO) — ⚠ aggregator-only (no customer-side evidence)

Most recent 10-K (FY 2025, filed 2025-05-19, accession 0001604778-25-000041, primary doc rfmd-20250329.htm): zero hits for Tower / TowerJazz / Jazz / Newport. Zero hits for TSMC and GlobalFoundries in the same scan. Qorvo’s 10-K language treats foundry sourcing generically.

Verdict: ⚠ aggregator-only. There is no customer-side 10-K language naming Tower as a Qorvo foundry partner. The aggregator framing in trade press has no customer-disclosure cross-confirmation.

C. Broadcom Inc. (AVGO) — ⚠ aggregator-only (TSMC named, Tower not)

Most recent 10-K (FY 2025, filed 2025-12-18, accession 0001730168-25-000121, primary doc avgo-20251102.htm): zero hits for Tower / TowerJazz / Jazz / Newport. Six hits for TSMC. Broadcom names TSMC as a foundry counterparty in its risk-factors language; no Tower attribution.

Verdict: ⚠ aggregator-only. Tower-Broadcom is plausible at the trade-press level but explicitly not customer-side disclosed. AVGO’s specialty-process needs (SiGe BiCMOS for legacy Broadcom-Avago lines) could plausibly hit Tower, but the disclosure threshold for AVGO at $54B+ revenue is high enough that any such relationship would be sub-material.

D. Semtech (SMTC) — ⚠ aggregator-only (silent)

Most recent 10-K (FY 2026, filed 2026-03-23, accession 0000088941-26-000005, primary doc smtc-20260125.htm): zero hits for Tower / TowerJazz / Jazz / Newport / TSMC. Five hits for “foundry” (generic). Semtech’s 10-K does not name any specific foundry counterparty.

Verdict: ⚠ aggregator-only.

E. Murata Manufacturing — ⚠ aggregator-only (no SEC filing)

Murata is Japanese-listed and does not file SEC 10-K or 20-F. EDGAR full-text search returns no Murata SEC document referencing “Tower Semiconductor” / “TowerJazz”. General web search yields no Tower-Murata primary disclosure (Murata’s RF-FEM business is largely vertically integrated post-Peregrine acquisition).

Verdict: ⚠ aggregator-only.

F. Texas Instruments (TXN) — ⚠ aggregator-only (silent — TI is largely internal-fab)

Most recent 10-K (FY 2025, filed 2026-02-06, accession 0000097476-26-000059, primary doc txn-20251231.htm; CIK 0000097476): zero hits for Tower / TowerJazz / Jazz / Newport / TSMC. One generic hit for “foundry”. TI runs internal fabs (Sherman TX, Lehi UT, Richardson TX, Dallas TX, Aizu-Wakamatsu Japan) and outsources only at the margin.

Verdict: ⚠ aggregator-only. Tower-TI is structurally implausible at meaningful volume given TI’s internal-fab footprint.

G. ON Semiconductor (ON) — ⚠ aggregator-only (silent — ON is largely internal-fab)

Most recent 10-K (FY 2025, filed 2026-02-09, accession 0001097864-26-000006, primary doc on-20251231.htm): zero hits for any trigger phrase. ON also runs an extensive internal-fab footprint (East Fishkill NY 300mm, Pocatello ID 200mm, Gresham OR 200mm, Roznov Czechia, Nampyeong Korea, Niigata Japan).

Verdict: ⚠ aggregator-only.

H. Analog Devices (ADI) — ◐ partial via Maxim succession

Maxim Integrated FY 2021 10-K (filed 2021-08-20, accession 0000743316-21-000025, primary doc mxim-20210626.htm): Maxim’s 10-K explicitly names “TowerJazz Texas, Inc. (formerly known as TJ Texas, Inc.) (TowerJazz), an indirect wholly-owned subsidiary of Tower Semiconductor Ltd.” as the wafer-supply counterparty for the November 18, 2015 long-term supply agreement that accompanied the sale of Maxim’s San Antonio TX (Fab 9) facility to Tower. The agreement obliges Maxim to procure specified quantities of silicon wafers from TowerJazz on long-term terms. Maxim was acquired by ADI on August 26, 2021 — the supply agreement passed through to ADI by operation of the merger.

ADI FY 2025 10-K (filed 2025-11-25, accession 0000006281-25-000153, primary doc adi-20251101.htm): zero hits for Tower / TowerJazz / Jazz / Newport / San Antonio. ADI does not separately disclose the Maxim-Tower agreement in its 10-K — likely because it is below ADI’s materiality threshold post-merger ($9-12B revenue base).

Verdict: ◐ partial. The Tower-Maxim long-term supply agreement is verified primary at Maxim’s last standalone 10-K (FY 2021). ADI inherits the contract by succession; ADI’s own 10-K disclosure has been genericized but the underlying obligation is presumed to continue absent any public counter-disclosure. The Maxim 10-K language is sufficient to cite ADI as a confirmed Tower customer with the partial qualifier reflecting “via Maxim succession, not separately re-disclosed by ADI”.

I. Lattice Semiconductor (LSCC) — ✗ excluded

Most recent 10-K (FY 2025, filed 2026-02-13, accession 0001437749-26-004100, primary doc lscc20260103_10k.htm): Lattice explicitly names its foundry partners as UMC, USJC (Fujitsu/UMC Japan), Samsung Semiconductor, TSMC, and Seiko Epson. Tower is NOT in the list. Lattice’s foundry roster is fully disclosed and Tower is structurally absent.

Verdict: ✗ excluded. Lattice should be removed from any aggregator-style “Tower customer” speculative list.

J. Cirrus Logic (CRUS) — ✗ excluded

Most recent 10-K (FY 2025, filed 2025-05-23, accession 0000772406-25-000014, primary doc crus-20250329.htm): zero hits for Tower / TowerJazz / Jazz / Newport. Two hits for TSMC. Cirrus Logic’s audio / sensor IC volume runs at TSMC (and historically at SMIC for older nodes); no Tower relationship surfaces in the 10-K.

Verdict: ✗ excluded.

Bonus findings (not in the priority list but surfaced during the sweep)

B1. Vishay Intertechnology (VSH) — ✓ verified-primary

FY 2022 10-K (filed 2023-02-22, accession 0000103730-23-000013, primary doc form10k.htm): the financial-statement footnote on Semiconductor Foundry Agreements explicitly states Vishay’s Siliconix subsidiary has maintained long-term foundry arrangements with Tower Semiconductor since 2004, with a technology-transfer component plus minimum wafer-purchase commitments under an 18-month rolling forecast. The disclosed minimum purchase commitments tied to Tower were $48,073K (2023) + $15,287K (2024).

FY 2023+ 10-Ks: Vishay’s disclosure language was streamlined; the explicit “Tower Semiconductor” foundry-agreement paragraph drops out of the FY 2023 (filed Feb 2024), FY 2024 (filed Feb 2025), and FY 2025 (filed Feb 2026) 10-Ks. The Newport mentions in those years all refer to Vishay’s March 2024 acquisition of “Newport Wafer Fab” in South Wales (UK) — distinct from Tower’s Newport Beach (CA) Fab 3. Whether the Tower-Siliconix commitment terminated, was rolled into a generic foundry-commitments line item, or simply fell below the new disclosure threshold post-Newport-UK acquisition is not separately disclosed.

Verdict: ✓ verified-primary as of FY 2022; ⚠ unconfirmed-current (post-FY 2022 status not customer-disclosed).

B2. Impinj (PI) — ✓ verified-primary

FY 2021 10-K (filed 2022-02-14, accession 0001564590-22-004981, primary doc pi-10k_20211231.htm): explicitly states Tower Semiconductor (renamed in 2020 from TowerJazz) “fabricates our reader IC wafers in the United States and has been our sole reader IC wafer supplier since 2008”, on a purchase-order basis without a long-term agreement. Impinj’s reader-IC silicon volumes are 100% Tower-sourced as of this disclosure.

FY 2023+ 10-Ks: the explicit “Tower” reference is removed in favor of generic “foundry partners” language. No public severance disclosure; no public diversification-event disclosure. Impinj’s reader business may have diversified or may simply have streamlined the disclosure.

Verdict: ✓ verified-primary as of FY 2021; ⚠ unconfirmed-current.

B3. Inphi (now Marvell MRVL) — ✓ verified-primary

FY 2019 10-K (filed 2020-03-02, accession 0001437749-20-004130, primary doc iphi20191231_10k.htm): Inphi’s principal foundries are explicitly named as TSMC, WIN Semiconductors, TowerJazz Semiconductor Ltd. (in North America), and GlobalFoundries (in North America). Tower is one of four principal foundries. Inphi was acquired by Marvell on April 20, 2021; Marvell’s high-speed analog and SerDes-on-PHY business is the lineal successor.

Verdict: ✓ verified-primary at Inphi’s last standalone 10-K. Marvell’s own 10-K does not separately disclose the Tower relationship (parent-level scale dwarfs the legacy Inphi line). For TSEM customer-roster purposes, this is the cleanest verified primary attestation that Marvell-Inphi-lineage volume runs at Tower.

B4. O2Micro International (OIIM) — ✓ verified-primary

FY 2021 20-F (filed 2022-04-18, accession 0001171843-22-002617, primary doc oiim20211231_20f.htm): explicitly names “TowerJazz Panasonic Semiconductor Co., Ltd. (Tower Semiconductor)” as one of three top foundries (with VIS and CSMC) that manufactured “most” of O2Micro’s IC volume in 2021. TowerJazz Panasonic is the Tower-Panasonic Japan JV (TPSCo) — a Tower subsidiary, distinct from but parented by the same Tower Semiconductor Ltd. O2Micro is a Cayman-domiciled, Taiwan-headquartered fabless power-management IC company.

Note: O2Micro’s last public 20-F is FY 2021 (filed April 2022). The company’s subsequent ownership status (delisted / privatized / merged) is uncertain; the FY 2021 disclosure is the most recent customer-side primary source.

Verdict: ✓ verified-primary as of FY 2021.

Could not be verified — these stay ⚠ aggregator-only

The following remained at ⚠ aggregator-only after this verification pass — either because the customer files no SEC document (foreign issuer with no ADR depositary registration), or the 10-K is silent on Tower / TowerJazz / Jazz / Newport, or the customer is structurally an internal-fab IDM that uses external foundries only marginally:

  • Murata Manufacturing — Japanese-listed, no SEC filing; no English-language primary disclosure of Tower relationship located.
  • Samsung Semiconductor / Samsung Electronics — Korea-listed; primarily internal-fab; no English-language primary disclosure of Tower relationship located.
  • Infineon Technologies — German-listed; primarily internal-fab; no SEC filing; no primary disclosure of Tower relationship.
  • Renesas Electronics — Japan-listed; primarily internal-fab; publicly-disclosed foundry alliance is with GlobalFoundries (expanded Feb 2025 per industry trade press); Tower not named in Renesas IR materials.
  • NXP Semiconductors (NXPI) — files 10-K; FY 2024 10-K silent on Tower; primarily internal-fab.
  • Texas Instruments (TXN) — files 10-K; FY 2025 10-K silent on Tower; primarily internal-fab.
  • ON Semiconductor (ON) — files 10-K; FY 2025 10-K silent on Tower; primarily internal-fab.
  • Qorvo (QRVO) — files 10-K; FY 2025 10-K silent on any specific foundry partner.
  • Broadcom (AVGO) — files 10-K; FY 2025 10-K names TSMC, silent on Tower.
  • Semtech (SMTC) — files 10-K; FY 2026 10-K silent on Tower.
  • Teledyne Technologies (TDY) — files 10-K; EDGAR full-text search returns 0 hits for “Tower Semiconductor” against TDY CIK; silent on Tower.

These stay ⚠ aggregator-only in customers diversified. Aggregator-level naming should not be promoted to thesis files without a primary-source customer-side or Tower-side cross-confirmation.

Excluded — these should be removed from any aggregator list

These customer names were structurally rejected by the customer’s own foundry-roster disclosure and should not appear in any future Tower-customer aggregation:

  • Lattice Semiconductor (LSCC) — FY 2025 10-K names UMC + USJC + Samsung + TSMC + Epson as foundry partners; Tower NOT in roster.
  • Cirrus Logic (CRUS) — FY 2025 10-K names TSMC; no Tower reference.

  1. Vishay Tower-Siliconix commitment, current status (FY 2023 onward): the explicit Tower disclosure dropped from VSH’s 10-K starting with FY 2023. Whether the underlying 2004 long-term agreement is wound down, retained at sub-disclosure-threshold, or rolled into a generic foundry-commitments line is unresolved. Suggested follow-up: review VSH 10-Q filings 2023-2026 for any references to “Tower” or “Siliconix foundry”; check VSH proxy or earnings-call commentary for FY 2023-2025 Tower mentions.

  2. Impinj Tower-foundry, current status (FY 2022 onward): similar pattern — explicit Tower reference dropped after FY 2021. Whether Impinj diversified or simply genericized is unresolved. Suggested follow-up: check Impinj investor-day decks or earnings-call transcripts 2022-2026 for foundry commentary; check 8-K filings around 2022-2024 for any major foundry-supply-agreement event.

  3. ADI / Maxim Tower supply agreement, post-merger continuation: Maxim’s FY 2021 10-K is the last public document with the explicit TowerJazz Texas language. ADI’s own 10-K does not re-disclose. Whether the Nov 2015 long-term supply agreement was extended, modified, or wound down post-Aug 2021 ADI merger is unresolved. Suggested follow-up: check ADI 8-K filings 2021-2026 for any reference to TowerJazz Texas or San Antonio Fab 9; review Tower’s own 6-K and 20-F filings for any reference to ADI as a successor counterparty (Tower has not, to date, named ADI individually).

  4. Top-4 unnamed customers in Tower’s FY 2024 20-F (27% of revenue combined): this remains the single most actionable open audit item. Plausible candidates from the verified set (Vishay, ADI-via-Maxim, Marvell-via-Inphi, Skyworks, Impinj, O2Micro) provide a portion of the customer mix but none individually triangulate to a 3-11% revenue band without further volume disclosure. Suggested follow-up: customer-side investor-day cross-references; customer-side 8-Ks announcing capacity commitments at Tower; Tower 6-K filings around quarter-ends for design-win disclosures.

  5. Skyworks current 2026 status: Skyworks’s modern 10-K language is generic. The 2012 Foundry Supplier of the Year award is fourteen years old; volume and process-allocation status in 2026 is not customer-disclosed. The pending Skyworks-Qorvo merger (announced 2025) compounds the unknown. Suggested follow-up: monitor Skyworks-Qorvo merger close documents (8-K) and any subsequent foundry-roster disclosures; review Tower’s own 6-K filings for any Skyworks-named announcements.

Methodology footnote

EDGAR full-text search (efts.sec.gov/LATEST/search-index) was used with the phrases “Tower Semiconductor”, “TowerJazz”, “Jazz Semiconductor”, “Jazz Technologies”, “Newport Fab” — both broadly (across all 10-Ks since 2018) and per-CIK (each priority-list CIK individually). For each candidate customer, the most recent 10-K HTML was downloaded directly from the SEC archive and searched in full-text for all five trigger phrases plus “TSMC”, “GlobalFoundries”, “foundry” as control terms. The User-Agent header was set to “TSEM Research ward@elst.be” per SEC API guidance.

Where a customer’s most-recent 10-K was silent on Tower but an older filing (typically the year of acquisition or supply-agreement signing) was explicit, the older filing is cited as the verified-primary anchor with a “succeeded by…” annotation if a corporate-event has changed the legal counterparty.

Sources (consolidated)

Cross-references