Fund Manager Reveals the Strategy that Earned him a 2,000% Profit from a Single Stock

Defensive stocks in Europe have seen significant growth this year, with some of the leading companies tripling in value. However, one fund manager spotted the sector’s potential – particularly that of Rheinmetall – early on, which brought him substantial profits.

Christopher Hart manages the Global Premium Equities fund at Boston Partners, with assets totaling $5.8 billion. The fund’s net return from the beginning of 2025 through the end of July is 22%.

His team follows a value investing strategy, ignoring market noise and focusing on the so-called “three-circle rule”: only selecting stocks that have:

1. Attractive valuation
2. Strong fundamentals
3. Positive business momentum

If a stock no longer meets these three criteria – for example, due to an excessive rise in valuation or deteriorating fundamentals – the team sells it.

“We’ve had massive asset growth over the past 20 years by strictly adhering to our value investing style,” Hart told CNBC.

Fund Performance

In the first seven months of 2025, the fund outperformed the MSCI World Index, which delivered a 15.2% return over the same period. Hart emphasizes that he does not follow the index and often takes contrarian positions.

“We see the business as a glass half full, not half empty. We simply follow discipline – every day, with every stock we select.”

The Rheinmetall Bet

A typical example of a successful trade is Rheinmetall – the German weapons manufacturer. At the beginning of 2025, the fund fully sold its position in the company, even though investor interest continued to grow.

Since the beginning of 2025, Rheinmetall shares have risen by 209% due to the large-scale increase in military budgets across Europe.

Boston Partners began buying the stock back in 2019, when the company was still combining automotive components and defense. Over the following six years, Rheinmetall became one of the fund’s top 10 holdings, with a share of over 2%.

By the time of the complete sale, the company’s shares had increased by 2,056%.

“Rheinmetall was our largest position and probably the best-performing stock in the history of the fund,” says Hart.

He explains that the investment was made before the war in Ukraine – at a time when most defense companies in Europe did not meet the fund’s criteria. Rheinmetall, however, was an exception.

“We liked their fundamental metrics. Then Ukraine happened, and things accelerated.”

Sale despite the rally

Hart explains that the fund has a discipline when it comes to selling – as soon as the valuation exceeds the intrinsic value, they sell, even if the price continues to rise.

“If a company turns into a growth stock, that’s no longer our style. We’re not here for ‘growth’.”

Value Investing

Value investing – the search for intrinsically undervalued stocks – is not suitable for everyone. Although it is the foundation of Warren Buffett’s success, some argue that it causes investors to miss out on big gains from growth companies.

In 2024, Boston Partners’ fund returned 10.7% (before fees), while the S&P 500 rose by 23.3%. In 2025, the index is already up by 12%.

Some, like Greenlight Capital founder David Einhorn, claim that value investing is “dead” because money is flowing into index funds.

However, Hart rejects these claims:

“There have been many periods when ‘value’ looks dead – but every time, it turns out it’s not.”