Our alumnus Dr Florian Sonnenburg has a degree in economics from the University of Wuppertal. In 2010, he continued his career at the University of Cologne, where he worked at the Department of Finance (Professor Dr Alexander Kempf) at the WiSo Faculty, first as a research assistant and then, after completing his doctorate in 2016, as an academic counsellor. In 2020, he gave up his appointment as civil servant for life and founded the investment boutique Sonnenburg Investments. He expanded the analysis model developed in his thesis, which can be used to systematically identify undervalued quality companies at an attractive price, to successfully invest not only as a private individual but also on behalf of the Applied Science Equity Fund advised by Sonnenberg Investments. In our alumni interview, we talked to him about his first entrepreneurial steps as a child, the influence of his role model Warren Buffett on his alalysis model, and about the Master's seminar ‘Applied Equity Research’, in which students can win Deutschlandstipendien for their university.

Dear Dr Sonnenburg, you started buying shares at the age of 17. Where does your fascination for investments and the capital market come from?

I was interested in finance and economics from an early age. At the time, my brother and I organised a bicycle race - a mini version of ‘Rund um Köln’ for the children in our street. We borrowed 100 marks from our parents and bought sausages, charcoal, drinks and salads from wholesalers.

We promised the corner kiosk owner an advertising banner along the route if he gave us a keg of Kölsch beer in return. He probably didn‘t need the publicity, but I think he liked our entrepreneurial spirit. We also held a raffle with small prizes and gave home-made trophies to the winners. While the kids were giving everything they had on the track, the parents bought raffle tickets, Kölsch beer and sausages - an all-round successful day for young and old.

In the end, we paid back our ‘loan’ to our parents and used the small profit to supplement our pocket money. Inspired by this, we even opened a snack bar in the carport - without a licence, but with a lot of enthusiasm. The business was not a success. But this small failure at such a young age only increased my enthusiasm for economic matters.

I was probably the only student in my year who read the Financial Times Deutschland every morning – a bit nerdy in retrospect, but absolutely my thing. My enthusiasm was really sparked when I came across Warren Buffett's investment approach. The idea of delving deep into business models and investing in quality companies over the long term fascinated me back then - and still does today. As a result, I bought my first shares at the age of 17 - and my passion for the capital market has stayed with me ever since. I still hold some of those shares today.

After graduating from the University of Wuppertal, you decided to pursue an academic career at the WiSo Faculty. What were the reasons for this? Why didn't you go to the financial centre Frankfurt with this good scientific education?

I felt that people in investment practice were often thinking too short-term - that didn't fit with my mindset. I was strongly influenced by Warren Buffett and had developed a model in my thesis based on his approach to identify undervalued quality companies. At the same time, I was inspired by the scientific way of working: critical thinking, working independently in a structured way and in-depth analysis. The opportunity to do my PhD with Prof Kempf at the WiSo Faculty was therefore a stroke of luck for me - and a decisive phase in my development.

The Applied Science Equity Fund is closely linked to your investment boutique Sonnenburg Investments, which you founded in 2020. For all non-financial experts: Can you explain what exactly this is?

The Applied Science Equity Fund is an equity fund in which we consistently apply the principles of value investors such as Warren Buffett: We invest long-term in quality companies that are attractively valued and whose business models we understand in detail.

Applied Science stands for our science-based investment approach - in two clear steps: First, we use a pre-selection model based on my doctoral thesis, which has been continuously developed since then. It uses scientific criteria to identify undervalued quality companies. This is followed by in-depth research using a structured checklist that systematically analyses key aspects such as business model, financial stability and competitive advantages. Both the model and the checklist have been developed and refinded over many years and are difficult to replicate in this depth and combination.

Despite founding Sonnenburg Investments and your success as a portfolio manager, you are still closely associated with the University of Cologne and the WiSo Faculty, regularly offering the master's course ‘Applied Equity Research’ - a direct link between teaching and practice in finance that is rather rare in academic education. Could you describe this in more detail? And what is the motivation?

With the Applied Equity Research seminar, we enable students to apply research-based investing in a practical way. Over a period of three months, they independently analyse a real company and produce a comprehensive research report. We guide them every step of the way.

The analysis process is based on our fund approach: scientifically sound, fact-based, structured - with the aim of really understanding business models. This gives students first-hand experience of how our approach to company analysis works.

The seminar grew out of two observations that have been on my mind for some time: This type of teaching has long been standard in the US - but is still the exception here in Germany. At the same time, studies show how strongly such formats promote financial literacy, critical thinking and career preparation. The feedback has been overwhelmingly positive - and it’s great for me to see how much enthusiasm for long-term investing is generated. This is our contribution to practical financial education.

In addition to the University of Cologne, you also offer the master's course ‘Applied Equity Research’ at the University of Wuppertal, the Technical University Dortmund and the University of Bielefeld. The special thing about it: At the end of the semester, each of the four universities sends a team to a final day where the students present the company they have analysed during the semester. What motivates the students to take part in this competition, besides the great opportunity to present themselves to a jury of experienced executives from the investment industry?

The final day is a real highlight for the students. Presenting their analysis to a jury of experienced industry professionals is a rare opportunity that challenges them professionally and offers real visibility. The experience of the seminar pays off: One participant was able to skip a round of interviews thanks to his research report and is now working as a fund manager. Another became an assistant to a board member of one of our practice partners as a result of his presentation. We have also been able to arrange numerous other internships, working student positions and entry-level jobs.

In addition to the learning effect and career opportunities, there is another incentive: depending on their ranking, the universities receive funding that directly benefits the students. As the winner of the last final day, the WiSo team, for example, received a grant of €7,200, which this year will be paid out in the form of four Deutschlandstipendien for the University of Cologne.

You are offering the master's course again this year. What are your expectations for the final day in 2025? Will the competition in 2025 be more demanding due to new challenges or impulses?

First of all, I am delighted that this year's final day will see an even higher level of funding. As our fund grows, so does the amount of funding. Because we have been able to attract many new investors, the amount of funding this time is around €20,000 - a strong additional motivation for the students.

The competition is also getting tougher: Cologne wants to continue its winning streak, other universities want to attack. At the same time, we are continuing to develop the programme’s framework. I am particularly looking forward to the presentations by our practice partners DEVK Versicherungen and the Kirchliche Zusatzversorgungskasse des Verbandes der Diözesen Deutschlands (KZVK). Especially in the current capital market environment, they offer valuable insights into the perspective of large institutional investors - practical and relevant for the students.

The programme will be complemented by scientific impulses and a start-up lecture to convey new approaches and entrepreneurial perspectives. We want to offer the students another special day - so that by the end they realise: This was more than just a seminar.

Dr Sonnenburg, l, thank you very much for your time and for this interview.