The Nuremberg native brings over three decades of capital markets experience, backed by a career shaped by deep market insight and a genuine passion for investing. His journey began in 1994 through an investment club among colleagues – a formative experience that sparked a lifelong dedication to identifying compelling investment opportunities.
Following senior editorial roles at Nürnberger Nachrichten, €uro am Sonntag, and €uro, he went on to serve as Editor-in-Chief of the renowned investor magazine Börse Online from 2014, where he played a key role in shaping high-quality financial journalism for a broad investor audience.
Since April 2026, he has been operating independently, fully focused on his core strength: uncovering mispriced equities with significant upside potential – particularly within the small- and mid-cap segment, where inefficiencies create attractive opportunities for discerning investors.
Throughout his career, he has engaged with some of the most influential minds in global finance, including Warren Buffett, Charlie Munger, Jim Rogers, and George Soros. The unique insights gained from these conversations continue to inform his analytical perspective today. As a dedicated value investor, he is committed to translating complex market dynamics into clear, actionable ideas – empowering investors to make better-informed decisions.
Commented by Jens Castner
Commented by Jens Castner on April 10th, 2026 | 08:15 CEST
Between Hubris, Hype, and Hardship: A.H.T. Syngas, 2G Energy, and SFC Energy in the Cleantech Battle
At a time when Donald Trump’s return to the White House is fueling the fossil fuel industry, innovative cleantech companies are vying for attention and investors. A.H.T. Syngas, 2G Energy, and SFC Energy embody the shift toward clean, decentralized energy supply—from hydrogen derived from waste to flexible fuel cells. On the stock market, these small-cap stocks are currently struggling, while defense stocks are riding high. But the rediscovery of sustainable business models is only a matter of time.
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Commented by Jens Castner on April 8th, 2026 | 08:10 CEST
YELLOW CAKE, KAZATOMPROM, AND STALLION URANIUM: THREE WAYS TO PLAY THE URANIUM BOOM
Nuclear power is poised for a boom worldwide. This promises bright prospects for the uranium market. What seemed politically dead is being mercilessly disproved by the reality of exploding energy demand for artificial intelligence and data centers. The price of uranium has more than tripled since 2016, and experts see further potential. For investors, there are three interesting but very different investment opportunities: from the solid stockpiler Yellow Cake to the global market leader Kazatomprom to the promising challenger Stallion Uranium.
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Commented by Jens Castner on April 2nd, 2026 | 10:50 CEST
Green Promises, Yellow Solutions: KWS Saat, MustGrow Biologics, and Corteva Under the Microscope
Greenwashing or Genuine Innovation? The debate over sustainable investments hits few industries as hard as agrochemicals. Companies like Corteva, KWS Saat, and MustGrow Biologics are working on technologies that have the potential to fundamentally transform agriculture. Whether through genetically optimized crops or natural mustard extracts: the race for more efficient and environmentally friendly farming methods is in full swing. This opens up exciting opportunities for investors.
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