What smart money is saying about Lumentum
2 funds in our archive have pitched Lumentum — most recently Blue Whale Growth Fund in June 2026.
Lumentum Holdings Inc., established in 2015 and headquartered in San Jose, California, is a global leader in optical and photonic product manufacturing. The company's reach extends across the Americas, Asia-Pacific, Europe, the Middle East, and Africa. Lumentum operates through two principal business units: Optical Communications (OpComms) and Commercial Lasers. The OpComms segment develops and supplies components, modules, and subsystems essential for transmitting video, audio, and data across high-capacity fiber optic networks. Its offerings encompass a wide range of products, including tunable transponders, transceivers, and transmitter modules, alongside various tunable lasers, receivers, and modulators. Furthermore, this segment provides critical transport products such as reconfigurable optical add/drop multiplexers (ROADMs), optical amplifiers, and optical channel monitors. A comprehensive suite of components is also available, featuring 980nm, multi-mode, and Raman pumps; switches; attenuators; photodetectors; gain flattening filters; isolators; wavelength-division multiplexing (WDM) filters; arrayed waveguide gratings (AWGs); multiplex/de-multiplexers; and integrated passive modules. Distinctive innovations from this segment include the Super Transport Blade, which integrates multiple optical transport functions into a single unit; vertical-cavity surface-emitting lasers (VCSELs); directly modulated and electro-absorption modulated lasers; and advanced laser illumination sources for 3D sensing systems. OpComms serves key clientele in the telecommunications, data communications, consumer, and industrial markets. Conversely, the Commercial Lasers segment produces an array of laser technologies, such as diode-pumped solid-state, fiber, diode, direct-diode, and gas lasers. These are primarily utilized in original equipment manufacturer (OEM) applications. This segment's laser solutions cater to a broad spectrum of markets and uses, including sheet metal processing, general manufacturing, biotechnology, graphics and imaging, remote sensing, and precision machining.
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Position history
Between Q3 2025 and Q3 2026, 16 fund letters reported a position in Lumentum — 8 opened or added to the position, 5 trimmed or exited.
| Quarter | Letters | Bought | Sold | Theses |
|---|---|---|---|---|
| Q3 2026 | 3 | 2 | 1 | 0 |
| Q2 2026 | 11 | 6 | 4 | 1 |
| Q1 2026 | 1 | 0 | 0 | 0 |
| Q4 2025 | 1 | 0 | 0 | 0 |
| Q3 2025 | 0 | 0 | 0 | 1 |
Fund activity · 16 positions · 13 moves
- September 2026
“We also added Ciena and Lumentum, reflecting rising optical connectivity requirements in AI data centers, and Seagate and Vertiv, which stand to benefit from demand for high-capacity storage and increasingly power- and cooling-intensive data center architectures.”
Lumentum - September 2026
“We used AI-related volatility to scale positions in networking companies like Lumentum, Credo Technologies and Astera Labs, broadening our AI exposure within technology.”
Lumentum - August 2026
“To fund this new position, we sold our holding in Lumentum, a US listed supplier of photonics and optical communications systems.”
Lumentum - New positionClearBridge Investments Growth StrategyJune 2026
“In addition to the transactions mentioned above, the Strategy initiated positions in Credo Technology and Lumentum in the IT sector.”
Lumentum - June 2026
“We added to Cisco Systems and Lumentum Holdings, reflecting our improving conviction in their respective wealth creation outlooks and attractive valuations.”
Lumentum - June 2026
“We continued to upgrade the portfolio, increasing exposure to areas where we see stronger long-term wealth creation opportunities and more attractive risk-reward characteristics. We added to Cisco Systems, Lumentum Holdings and Hannover Re, reflecting improving conviction in their respective wealth creation outlooks and attractive valuation support.”
Lumentum - June 2026
“We added to Cisco Systems and Lumentum Holdings, reflecting our improving conviction in their respective wealth creation outlooks and attractive valuations.”
Lumentum - June 2026
“We added to Cisco Systems, Lumentum Holdings and Hannover Re, reflecting improving conviction in their respective wealth creation outlooks and attractive valuation support.”
Lumentum - TrimmedBaron Technology ETFJune 2026
“We trimmed our positions in Datadog, Inc. and Lumentum Holdings Inc. following meaningful appreciation in both stocks that, in our view, left near-term upside more limited relative to our other holdings.”
Lumentum - TrimmedBaron Technology StrategyJune 2026
“Top net sales for the quarter Net Amount Sold ($M) NVIDIA Corporation 7.5 Solaris Energy Infrastructure, Inc. 3.0 Amazon.com, Inc. 2.8 Datadog, Inc. 2.2 Lumentum Holdings Inc. 2.0 We trimmed our position in NVIDIA Corporation, which had grown to represent an outsized share of the Strategy. The trim was a function of portfolio construction discipline rather than any change in our fundamental view — we remain strong believers in NVIDIA's long-term positioning as the dominant platform for AI compute. A portion of the proceeds was redeployed to add exposure to AMD and to memory semiconductor names, where we viewed as compelling risk/reward. We exited our position in Solaris Energy Infrastructure, Inc., which we discussed as a new position in our first quarter letter. The position accreted faster than we expected following our purchase, and after the stock's move, we concluded the remaining upside was more limited relative to other opportunities in the portfolio. We sold the position during the quarter and redeployed the proceeds elsewhere. We trimmed our position in Amazon.com, Inc. to add to Alphabet Inc., where we see a more compelling near-term risk/reward. We trimmed our positions in Datadog, Inc. and Lumentum Holdings Inc. following meaningful appreciation in both stocks that, in our view, left near-term upside more limited relative to our other holdings.”
Lumentum - New positionParnassus Investments Growth Equity FundJune 2026
“We continue to maintain a portfolio balanced between offense and defense. We have taken advantage of ongoing market volatility to selectively participate in secular trends at attractive valuations in AI beneficiaries including hyperscalers, semiconductors and data center and energy infrastructure. Due to the market concentration in mega-cap technology companies, the portfolio’s largest absolute weight continues to be the Information Technology sector, where we have an underweight position relative to the Russell 1000 Growth Index. The portfolio’s largest active weights relative to the Russell 1000 Growth are in Health Care, Communication Services and Materials. The portfolio has no exposure to Energy or Real Estate. We made several position changes during the quarter, selling six positions and adding five new ones. We also adjusted several position sizes in response to the Russell 1000 Growth Index reconstitution. In the Health Care sector, we see compelling long-term idiosyncratic growth opportunities in drug discovery, diagnostics and medical innovation. During the quarter, we added Twist Bioscience, a biotechnology company with a proprietary silicon-based DNA synthesis platform, and Revolution Medicines, developer of a promising new drug for pancreatic cancer. Other positions added during the quarter included Sandisk, a leader in flash memory solutions; Comfort Systems, a mechanical, electrical and plumbing contractor, which provides key labor for AI infrastructure build-out; and Lumentum, which makes optical products used in AI data center networking.”
Lumentum - June 2026
“Trading activity Having bought dislocation in the first quarter, we spent the second selling strength. Five of the quarter’s ten largest contributors were exited outright: SK Hynix, SanDisk, Applied Materials, Credo and Ciena, the last having doubled over the half year. The other five were reduced, among them Broadcom, Arm and Elite Material, and we also exited the first quarter’s standouts Lumentum and Vertiv, plus CoreWeave and Constellation Energy, alongside AppLovin, Newmont, Robinhood, SoFi and Upstart. With Boston Scientific, Shopify and Mercadolibre discussed above, the quarter’s dealing totalled seventeen positions sold and seventeen initiated: unusually high turnover for this Fund, and a deliberate response to the concentration above.”
Lumentum - June 2026
“The other five were reduced, among them Broadcom, Arm and Elite Material, and we also exited the first quarter’s standouts Lumentum and Vertiv, plus CoreWeave and Constellation Energy, alongside AppLovin, Newmont, Robinhood, SoFi and Upstart.”
Lumentum - June 2026
Listed in Munro Global Growth Small & Mid Cap Fund’s reported holdings.
Lumentum - March 2026
“The strong contribution from Lumentum, the US listed specialist laser and photonics equipment manufacturer, came largely through the dramatic increase in demand for optical networking equipment across AI infrastructure.”
Lumentum - HoldsAppleseedNovember 2025
“Within the equity portion of the portfolio, the biggest contributors to the Fund’s performance over the past 12 months were Lumentum convertible bonds, Fannie Mae preferred equities, AerCap (AER), Cameco (CCJ), and physical gold trusts.”
Lumentum
Also mentioned · 1
These funds discuss Lumentum — as a competitor, benchmark or comparable — without disclosing a position in it.
- MentionedBlue Whale Growth FundJune 2026
“Company: Lumentum Sector: Industrials Company Size: $67bn Powering the future of AI infrastructure with critical optical connectivity As AI clusters scale to unprecedented sizes, traditional copper interconnects are hitting physical limitations. Over even short distances, high-speed electrical signals become heavily distorted, requiring power-hungry booster chips that generate excess heat – a major bottleneck for power-constrained data centres. Lumentum provides the vital solution by converting data into light.”
Lumentum
Fund coverage · 2 theses
- Blue Whale Growth FundJune 2026
Lumentum is positioned as a leading optical connectivity supplier benefiting from AI cluster growth and the shift away from copper.
Read the full thesis - Baron Technology FundSeptember 2025
Lumentum Holdings Inc. is a leading photonics company poised to capitalize on the growing demand for advanced laser technologies in data centers and emerging markets driven by AI infrastructure.
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