Shares of Soitec SA tumbled 6.8% to €129.90 after UBS cut the French semiconductor materials maker to sell from neutral, setting an €85 price target that implies roughly 35% further downside. The call lands barely three weeks after Soitec posted fiscal 2026 results that sent shares surging 14% on a surprise cash-flow beat. For investors, the question is whether a single fast-growing product line can rescue a company whose core business is still shrinking.
• UBS Sees Margins Collapsing, Not Recovering
UBS slashed its fiscal 2027 gross margin forecast to 19.4% from 30%, citing continued inventory destocking that is driving elevated idle costs despite an expected revenue recovery.
The broker now expects diluted earnings per share of negative €0.11 in FY27, before rebounding to just €2 in FY28. For context, Soitec's gross margin already fell to 16.3% in FY26 from 32.1% a year earlier — meaning the factory-cost pain UBS fears is already visible. With roughly half the company's capacity sitting underused, every quarter of weak volume compounds losses.
• The Smartphone Business Is Still in a Hole
Mobile Communications revenue hit €309 million in FY26, down 41% year-on-year at constant currency , and the inventory glut is not clearing quickly. Customer wafer inventories at key foundries stood at 2 million units as of March 2026, unchanged from December 2025. Mobile still accounts for over half of sales, and Jefferies forecasts global handset units falling 19% in 2026 and a further 14% in 2027 , keeping any rebound well out of reach.
• Photonics Is Real but May Be Priced Beyond Reason
Photonics revenue crossed $100 million in FY26, "earlier than initially anticipated." That's genuine progress in making silicon wafers for optical connections inside AI data centers. But Soitec trades at 33.9 times FY27 EV/EBITDA — an 85% premium to peers like Coherent and Lumentum , according to Jefferies. UBS argues the market is paying growth-stock prices for a company that will post a loss next year.
• Structural Threats Lurk Beyond the Cycle
UBS highlighted shrinking smartphone wafer content per device, plus the expiry of a key licensing agreement with competitor GlobalWafers , which could let new rivals produce similar wafers. That undercuts the long-term pricing power investors are banking on.
Bottom line: Soitec's photonics story is compelling, but two straight sell-side downgrades in six days suggest Wall Street thinks the stock ran far ahead of fundamentals.