Kalray (+300% in 2026): the current fervor is less about established execution and more about a bet on a spectacular turnaround. After years of value destruction and a near-bankruptcy, the company radically overhauled its model, abandoning a capital-intensive industrial strategy to refocus on monetizing its intellectual property in DPUs—a key segment for data centers and AI. This pivot, validated by a structural partnership with OpenChip, has sent margins soaring and restored credibility to the narrative, while anchoring Kalray in a compelling story of European technological sovereignty. However, the market enthusiasm remains largely driven by expectations (OpenChip increasing its stake, model stabilization, sustainable profitability) rather than proven fundamentals, making it more of a highly speculative special situation than a firmly established AI play.

2CRSi (+255% in 2026): the appeal of 2CRSi stems from a rare alignment between the market narrative and operational momentum. The company has emerged as one of the few French pure players in AI infrastructure, fully capitalizing on the explosion in data center investment. Its niche positioning in custom high-performance servers, particularly those featuring liquid cooling, allows it to capture surging demand while offering significant energy savings—a clear value proposition for clients. Most importantly, the group is translating this opportunity into tangible results, with spectacular revenue growth and an expected improvement in margins, finally lending credibility to a model long considered fragile.

Riber (+217% in 2026): is the Bezons-based group living its best life? Riber relies on a mix that is more solid than speculative, but which is beginning to incorporate an anticipation premium. At its core lies the quality of a niche model based on highly specialized, high-value-added equipment. To this is now added direct exposure to major tailwinds (AI, data centers, photonics, defense) supporting demand. Above all, the market is now looking ahead to a potential change in scale with its "Rosie" technology in silicon photonics, perceived as a possible industrial turning point. However, the recent rally already bakes in part of this scenario, with a speculative dimension linked to ramp-up expectations and potential M&A interest, gradually shifting the case from a quality play to an anticipated rerating story.

Soitec (+199% in 2026): the Isère-based firm typically gives its shareholders vertigo, but the current phase is bringing back the smiles. After a depressive collapse in the share price (from 243 EUR in 2021 to 22.62 EUR in December 2025), the time for recovery has come. This return to favor is explained by a perceived disconnect between short-term fundamentals, which remain weakened (notably by persistent weakness in the mobile market), and a rerating potential linked to strategic growth drivers. The market is beginning to price in silicon photonics and optical architectures for AI (CPO), where Soitec could benefit from its positioning on certain substrates, leading to higher margins. This thesis is fueling a rapid resurgence of interest in the stock.

Semco Technologies (+66% in 2026): less visible than its four compatriots and with a more recent market history, the Hérault-based company also operates in the semiconductor space. Its proposition rests on a rare combination of niche positioning, industrial visibility, and financial discipline. The company operates at the heart of semiconductor "front-end" with its eChucks—critical, high-value components whose adoption creates long-term recurring revenue. Semco CEO Laurent Pelissier recently explained that his company benefits indirectly from major waves (AI, 5G, defense, automotive) while remaining protected by long qualification cycles and deep customer relationships. Following last year's IPO, the management team has heavily emphasized a controlled economic model focused on organic growth, self-funded investments, pre-planned capacity expansion, and a clear distribution policy.