A little over two months into 2026, the flagship index of the Paris stock exchange has returned to equilibrium after a bullish start to the year. The modest rebound initiated yesterday does not challenge the underlying trends observed in recent weeks. Let’s take a look at the top and bottom of the leaderboard, and the reasons why certain companies find themselves there.
Let’s start with the bad news.

Stellantis brings up the rear with a drop of more than 30% in just over two months. This fall follows a -40% in 2024 and a -25% in 2025. Suffice to say, the automaker has been the CAC 40’s problem child for some time. The new management team didn’t call their turnaround plan “Reset” for nothing. The group recently acknowledged, with a massive write-down, the resounding failure of its commercial and industrial strategy. It will take time and money to heal the wounds. The market is not yet ready to pay for the recovery, given the structural challenges facing the sector.

Capgemini follows, down 24%. This is quite rare for the French consulting group, even though it is also coming off two negative years (-16% in 2024 and -10% in 2025). Investors are wondering how the sector will be impacted by AI. It is clear that some of the basic services that service companies used to charge handsomely for may slip away in the future. The sector has tried to explain that it is a catalyst for AI, but with little success so far. The market does not place it among the winners of the technological upheaval.

Dassault Systèmes rounds out the podium of declines, with -24% in 2026. What a fall from grace for France’s leading software group! Again, AI is part of the story, but not the whole of it. Dassault Systèmes has suffered the fate of fallen angels, caught between a valuation that brooked no missteps and a string of bad news. Furthermore, the evident failure of its diversification into healthcare has yet to be digested. The poor stock performance (DSY is also a falling knife: third consecutive year in the red) has brought governance criticisms to the fore. Pressure finally led to the resignation of the emblematic Bernard Charlès, handing over the reins to Pascal Daloz, who faces a tough challenge.

At the other end of the spectrum, ArcelorMittal is up 35%. The steelmaker has carried out a refocusing and deleveraging that has caught the attention of the financial community in recent years. It has since been swept up by the resurgence of the so-called analog economy as opposed to digital. Tangible assets and control over supply sources are back in vogue. Metals and mining stocks are all the rage at a time when sovereignty once again depends on raw materials.

The Franco-Italian semiconductor group STMicroelectronics (+31%) is back in the spotlight. Long among the sector’s also-rans due to an overexposure to a struggling automotive sector and underexposure to the AI boom, ST is doing better. The group suffered from the classic cyclicality of semiconductors, without benefiting from the AI-driven surge enjoyed by its rivals. The trough has now passed, and while its earnings trajectory is not dazzling, it is on the rise.

There was a time when some investors thought watching paint dry was more exciting than investing in telecoms. Orange has proven otherwise since last year (+47% excluding dividends in 2025). And 2026 has started off strong, with the group posting a 25% gain, earning it third place on the CAC 40 podium. After delivering convincing results in recent quarters, the operator has been buoyed by investor enthusiasm for infrastructure, especially those enabling AI services. The likely reduction from four to three operators in the French market, which could ease competitive pressure, has also contributed to the company’s strong stock performance.