Lumentum and Applied Optoelectronics Drop 4% as Microsoft Fights Chinese Optics Ban

Lumentum (NASDAQ: LITE) fell 4% to $623.58 and Applied Optoelectronics (NASDAQ: AAOI) fell 4% to $53.89 in Thursday afternoon trading, after Microsoft and other companies met White House officials to push back against a proposed FCC ban on Chinese-made optical transceivers. The meeting happened on the evening of November 10, according to reports. Microsoft declined to comment.

The stocks' decline sits at the intersection of two pressures: a broad retreat in AI hardware names and a policy fight that directly targets the market these two companies were expected to win. Understanding why a regulatory draft moved share prices requires understanding what optical transceivers actually do — and who controls that supply.

What does the proposed FCC ban actually cover?

Optical transceivers are the modules that move data over fiber-optic cables inside AI data centers. Every time a training run shuffles data between GPUs, that traffic passes through transceivers. The FCC has drafted a rule that would bar new models of Chinese-made transceivers from U.S. data centers.

The draft's scope is narrower than a blanket ban. According to reports, several limits constrain what it would actually change:

• It covers only new Chinese models, not existing product lines.
• Installed equipment is exempted.
• There is no FCC vote date yet.
• A 3.2 terabit-per-second speed threshold is reportedly under consideration — and Morgan Stanley expects products at that speed to start ramping only in 2028.

That last detail matters most for investors. The 800G and 1.6T transceivers that currently fill Lumentum's and Applied Optoelectronics' order books may be unaffected by the rule as drafted. In plain terms: the ban, even if adopted, might not touch the products these companies sell today.

Why is Microsoft lobbying against it?

China holds an estimated two-thirds of the global optical transceiver market. For the hyperscalers building AI data centers, that concentration is a supply problem: restrict two-thirds of your vendor pool and expansion slows. Microsoft and the other companies told White House officials exactly that, reports say — the ban could slow data center buildouts.

For Lumentum and Applied Optoelectronics, the same concentration is the bull case. If Chinese supply contracts under an FCC rule, U.S. makers stand to pick up share and pricing power. Pushback from one of the largest buyers in the market works directly against that thesis.

Applied Optoelectronics has the most awkward exposure of all. Microsoft accounted for 28.8% of its revenue in 2025, which means the customer lobbying to keep Chinese parts available is also its single largest revenue source. The company's interests and its biggest client's interests are pulling in opposite directions.

Takeaway: the policy fight isn't abstract for these stocks — it cuts through their revenue base and their growth story at the same time.

What role did the broader AI selloff play?

The optics makers weren't falling in isolation. The retreat followed a shock at the top of the AI chip industry: on November 12, NVIDIA's (NASDAQ: NVDA) board announced that Jensen Huang had resigned as president, chief executive and board member. AI hardware names sold off across the board, and Lumentum and Applied Optoelectronics fell with them.

Lumentum also carries deal context. It is the target of Marvell Technology's proposed acquisition, which Reuters valued at $115 billion. A leadership change at the AI industry's anchor supplier adds a separate layer of uncertainty to any company whose fortunes ride on data center spending.

The selloff reversed a strong November 11 session, when CoreWeave's results had renewed the AI trade. Lumentum rallied 11% that day before turning lower.

Why did Coherent hold steady?

Coherent (NYSE: COHR) traded at $234.44 on Thursday, essentially unchanged — and it kept most of a 9% gain from November 11. The divergence with its two peers is instructive.

Lumentum and Applied Optoelectronics are the stocks investors pitch as direct beneficiaries of a Chinese transceiver ban. That framing ties them tightly to the policy outcome: good news for the ban is good news for them, and the White House meeting reads as bad news. Coherent's business is broader. Its photonics platform runs from materials and crystal growth through optics and lasers, and it also sells into industrial markets. That vertical integration leaves it less tied to any single optical-parts category, which may explain why it shrugged off a story that hit its peers.

There's an NVIDIA connection too. NVIDIA is a strategic customer of Coherent, through a multi-year supply agreement for its advanced lasers and optical networking products.

What do these companies actually make?

The three businesses overlap but don't mirror each other:

• Lumentum builds lasers, cloud transceiver modules and optical circuit switches, with pump lasers and switches leading its latest growth. It describes its optoelectronic capacity as "effectively sold out well into the future."
• Applied Optoelectronics sells transceivers to large hyperscale operators and runs a cable television broadband business, with manufacturing in Sugar Land, Texas; Taipei, Taiwan; and Ningbo, China.
• Coherent runs a vertically integrated photonics platform spanning materials, crystal growth, optics and lasers.

The CEOs have already staked out positions on Chinese competition. On an earlier earnings call, Lumentum CEO Michael Hurlston argued that Chinese rivals haven't proven themselves at scale: "I caution that many of the Chinese laser suppliers are not delivering in the market today, and we have not seen significant output from them to date." Coherent CEO Jim Anderson framed his company's edge around breadth: "We believe this breadth and depth differentiates us."

What comes next?

The next test is whether a published FCC rule keeps the proposed 3.2 Tbps speed threshold and the exemption for installed gear. A tighter rule could support pricing for U.S. suppliers; a postponed or narrowed one could weaken the entire share-gain thesis.

The demand side, at least, isn't in question yet. Applied Optoelectronics' management expects demand for its high-speed modules to exceed production capacity throughout 2027. NVIDIA's leadership change adds a separate risk for AI hardware names, Lumentum and Applied Optoelectronics included. The FCC's decision on Chinese transceivers will show how much of the U.S. supplier thesis actually holds up.