U.S. ban on AI data center optics sparks market reaction and Wall Street debate

Huo Xing Finance reports that on August 5, news of a potential U.S. restriction on imports of optical components from China for AI data centers has become the new trading theme for the optical module sector. U.S. equities reacted first overnight. Stimulated by the news, optical communication stocks including Marvell, Coherent, Lumentum, Applied Optoelectronics, and Corning surged collectively, with capital rapidly flowing into the U.S.-based optical communication supply chain. Meanwhile, A-share optical module stocks faced downward pressure today, with North American AI supply chain-linked names such as InnoLight, Eoptolink, and FiberHome attracting market attention. Wall Street’s latest views are beginning to diverge. Both Morgan Stanley and Citigroup released quick analyses on August 4, but with differing emphases. Morgan Stanley emphasized the positive implications for the U.S. optical communication supply chain. It argued that if the U.S. ultimately restricts Chinese optical transceivers from entering AI data center supply chains, non-Chinese suppliers stand to gain market share reallocation opportunities, with Coherent being the clearest beneficiary. AAOI and Fabrinet are also expected to capture part of the incremental demand. Lumentum’s upside is more indirect, primarily stemming from a potential extension of the EML laser supply constraint cycle; market concerns over impending supply relief and margin pressure may be delayed. However, Morgan Stanley also acknowledged that implementing such a ban would be highly challenging. Current non-Chinese supplier capacities are insufficient to meet AI capital expenditure demands, and key upstream materials such as InP substrates still involve Chinese supply chain participation. If the U.S. restricts Chinese optical modules, China could retaliate at critical material stages. Morgan Stanley even suggested a potential workaround: Chinese cloud providers increasing procurement of U.S.-made optical communication components. Citigroup’s assessment was more cautious. It argued that this potential ban is unlikely to become a simple, clear-cut rule. Seven of the world’s top ten optical transceiver companies are Chinese firms, supplying over 50% of high-speed optical modules to major U.S. cloud vendors; moreover, the AI optical module supply chain remains tight, with Chinese manufacturers maintaining advantages in cost, product iteration, and delivery capabilities. Citigroup expects that under current supply-demand constraints, policy exemptions are highly likely. For Chinese companies, Citigroup ranked the impact as follows: FiberHome faces the most indirect effect, Dongshan Precision is moderate, and Eoptolink is most directly exposed. FiberHome primarily supplies passive components to overseas optical module firms, with limited short-term impact; Eoptolink benefits from approximately 88% of its 2025 revenue coming from Thailand, providing overseas production buffer capacity. The real concern lies in whether U.S. policy will further extend restrictions to Chinese-backed production facilities in third countries. This explains the market’s divergence: U.S. stocks are pricing in order reallocation expectations, while A-shares are pricing in compliance risks and valuation discounts related to North American clients. From both reports, Wall Street’s current consensus is clear: if implemented, the ban would briefly benefit valuation re-rating of the U.S. optical communication chain. The divergence lies in whether order migration can proceed smoothly. AI data center construction continues to accelerate, and cloud vendors require stable, low-cost, high-speed supply chains. Policy can alter expectations, but final outcomes are determined by capacity, certification, yield, and material supply. For the optical module sector, the market is now focusing not just on the headline of the ban—but on three key developments: whether final rules cover third-country production capacity; whether North American cloud vendors reallocate orders; and whether Chinese suppliers’ overseas factories can continue serving as a buffer.