Sivers Semiconductors: After a Giddy Record High, a 12% Plunge as Short Sellers Dig In

Sivers stock hit €10.23 then crashed 28% in a day after GlobalFoundries deal. Short interest at 6.65%, analysts cautious as revenue drops 22%. AGM on June 15, 2026.

The whiplash in Sivers Semiconductors shares has been brutal. On Wednesday, the stock hit a fresh 52-week high of €10.23, riding the euphoria of a strategic tie-up with US chipmaker GlobalFoundries in silicon photonics for AI data centers. By Thursday, the rally had vaporised: the stock tumbled 12% to €7.39, slicing roughly 28% off the peak in a single session. The annualised 30?day volatility stands at a staggering 245%, and the stock still trades 95% above its 50?day moving average of €3.79 — a clear sign that momentum has shifted from long?term narrative to short?term positioning games.

The catalyst for the original surge was the June 2 announcement that Sivers will supply laser arrays for GlobalFoundries’ silicon?photonics platform, targeting the market for pluggable optics that is expected to balloon to US$25 billion by 2030. The technology covers co?packaged optics and linear pluggable optics for AI?driven data?center architectures. Yet the official release offered little in the way of concrete financial projections. Both companies declined to elaborate when pressed by Swedish financial site EFN, leaving analysts to guess at the revenue potential.

A look at the Swedish Financial Supervisory Authority’s short?selling register shows why the bears are in no rush to capitulate. Net short positions still total 6.65% of the free float. Among the biggest players, Qube Research & Technologies holds 0.56%, having dipped below the 0.5% disclosure threshold on June 2 only to reappear again. Voleon Capital Management trimmed its position from 2.02% to 1.95%, while Two Sigma Investments edged up from 2.18% to 2.20%. A Finwire report noted that the aggregate short ratio actually fell from 7.82% to 6.57% after Tuesday’s 60% rally, but the adjustments are more tactical than a broad retreat.

Analyst scepticism reinforces the cautious tone. Redeye’s Jacob Benon describes the GlobalFoundries deal as positive but far from a game?changer, setting a price target of SEK 6.20 — roughly 26% below Thursday’s close. Affärsvärlden went further, pointing out that GlobalFoundries itself had previewed the partnership a month earlier, making the market frenzy look overheated. Since a March low of €0.27, the stock has multiplied more than thirtyfold, and year?to?date it is up over 20 times. With the relative?strength index at 66.2, the stock is not yet overbought, but the valuation rests entirely on hopes for future revenue.

The latest quarterly numbers offer a sobering counterpoint. First?quarter revenue slid 22% to SEK 61.9 million, the adjusted operating result came in at a loss of SEK 13.8 million, and operating cash flow was negative SEK 49.2 million. Management blames the US government shutdown in 2025 and currency?exchange headwinds, but the project pipeline grew 77% to US$799 million. For now, the disconnect between promise and financial reality remains wide.

All eyes now turn to the annual general meeting scheduled for June 15, 2026, in Stockholm. Shareholders will vote on the annual accounts, board discharge, and a convertible?bond proposal. Until then, the share price is likely to remain hostage to daily short?register updates and the mood of momentum traders, who are proving far more influential than the long?term photonics story.