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Frank Thelen Opens Up: The One Decision That Cost Me €100 Million

Irish Economy ✍️ Hans-Peter Keller 🕒 2026-03-07 21:36 🔥 Views: 1
Frank Thelen in an interview

We know him as the savvy investor from 'Dragon's Den', the tech visionary always with his finger on the pulse. But now, Frank Thelen is showing a completely different side of himself. In an exclusive interview, the 48-year-old gets down to brass tacks and confesses to a mistake that cost him dearly – really dearly. We're not talking a few thousand euro here, but a sum that's beyond the pale for most people: €100 million.

The Decision That Still Haunts Thelen

It wasn't a panic reaction, no hasty sale. It was a rational decision, made at a moment when Thelen thought the risk was just too high. We're talking about an investment he didn't make. A young company, promising technology – but Thelen hesitated, pulled his capital back, left the founders high and dry. Today he knows: it was the biggest blunder of his career. "That company later became one of the most successful players in the market. My stake would be worth about €100 million today," he explains with a mix of self-deprecation and reflection. It's one of those stories that makes every investor break out in a cold sweat – the missed opportunity, the one that got away.

Thelen isn't naming the company, but insiders whisper it could be a European tech start-up that landed Series A funding from a US giant shortly after he passed. One thing's for sure: the sting is still there. "It's not just the money. It's knowing that I simply wasn't brave enough in that moment. And I'm always preaching the opposite: courage and foresight."

From Rags to Riches and Back Again?

Frank Thelen's story is essentially one long success story. From school dropout to self-made millionaire, from tech geek to the most sought-after investor on German telly. With his investment company Freigeist Capital, he's put money into dozens of start-ups, some of which became genuine unicorns. He was one of the first to back e-mobility and clean energy while others were still debating combustion engines. His keynotes are legendary, his books bestsellers. And yet, the €100 million mistake shows: even the greats have their blind spots.

But Thelen wouldn't be Thelen if he didn't learn from his defeats. He's analysed the error meticulously: Why did he hesitate back then? What were the specific signals that threw him off? His conclusion is as simple as it is striking: "I focused too much on the short-term risks and underestimated the long-term potential. You can't approach disruptive technologies with a conservative mindset."

His Top Current Stock Picks

Even though the €100 million decision still lingers, Thelen is looking ahead. He remains a fervent advocate of future technologies. When asked where he'd put his money today, he doesn't hesitate for a second. He names three areas that he believes have the potential to change the world – and deliver juicy returns for investors:

  • Artificial Intelligence & Semiconductors: Thelen is convinced the AI boom is only just beginning. He considers companies like Nvidia or ASML solid anchors, but also recommends keeping an eye on European AI development hubs. "The next Google and Facebook are coming from Europe – I'm sure of it."
  • Quantum Computing: An area that still sounds like science fiction to most, but for Thelen, it's already ushering in the next industrial revolution. "Quantum computers will calculate things that today's supercomputers would need millennia for. Getting in early there could yield profits similar to those of early Microsoft shareholders."
  • Green Hydrogen Technologies: Thelen has always been a fan of clean energy. His focus now is on companies that are making hydrogen usable not just as fuel, but as storable energy for industry and households. "That's going to be the game-changer for the climate – and for savvy investors."

Of course, he also warns against blind actionism: "Just because I mention a stock doesn't mean you should buy it all tomorrow. You need to understand the business model, know the people behind it. And you need patience." It's precisely this patience that he lacked a few years ago – a lesson he now passes on to his children and young founders.

The Dragon Stays Hungry

Despite the million-euro faux pas, Frank Thelen isn't bitter. He sees the loss as part of the game, a ticket into an exclusive club of investors who all have their scars. He'll continue to enrich 'Dragon's Den', and start-ups will keep seeking his advice. And the €100 million? "I'll make it back," he says with a wry smile. "Maybe with the next quantum start-up. Who knows."

One thing is certain: anyone who's ever experienced Frank Thelen knows he doesn't give up. He remains the hunter, the dragon, always on the scent of an opportunity. And that's precisely what makes him so fascinating for us viewers and for the start-up scene – despite, or perhaps because of, his missed millions.