Is Mark Mobius’ reign as a king of emerging-market stocks coming to an end?

For a quarter of a century the name Mark Mobius has been synonymous with investing in developing markets. A bald, energetic, New York native who often dresses in white suits, Mobius is constantly encouraging investors to put money into fast-growing developing economies. In the US he was voted by his peers onto a list of the top 10 investors of the 20th century, putting him alongside Warren Buffett, Julian Robertson and George Soros. What Bill Gross was to bonds, Mobius was to emerging markets: the King.

His reign may be coming to an end. Like Gross, Mobius, 78, has posted mediocre numbers and seen investors depart. While they still make money, 11 of the 13 largest funds that Mobius oversees at Franklin Templeton Investments have underperformed their benchmarks over the past five years. At his zenith in 2011, Mobius oversaw $39 billion. Today that figure is down to $26 billion. And in December, his flagship Asian Growth Fund lost its long-held position as the region’s largest to First State Investments’ Asia Pacific Leaders Fund.

In an email, Mobius wrote, “We go into markets when others are fleeing, and while some of our fund performance has struggled at certain points in time, we believe that with our contrarian approach, our shareholders will be rewarded in the long term.”

Mobius joined Templeton, Galbraith & Hansberger in 1987, when investing in developing countries was still a novel idea. After being tapped by firm founder John Templeton to manage the Templeton Emerging Markets Fund, the company’s first foray into that territory, Mobius developed a reputation for sniffing out stocks that are undervalued relative to their growth potential.

He still crisscrosses continents 250 days a year, feeding on-the-ground research to his team of 50 money managers, analysts and researchers in 18 offices worldwide handling day-to-day operations of the more than 30 funds he oversees.

The last half-decade has been a struggle for the group, which has made ill-timed bets on energy and mining companies while underinvesting in technology stocks. As of March 31, Templeton Asian Growth held 33% of its assets in energy and material stocks, which account for only 9% of the fund’s benchmark, the MSCI AC Asia ex Japan index. The fund has gained 4.3% annually over the past five years, compared with 8.1% for the index. It’s trailed 44 of 46 similar funds with assets of at least $500 million over that same time span.

One of the fund’s largest holdings, the stock of Sesa Sterlite, India’s top aluminium producer, has tumbled 51% in the past five years as slowing growth in China cut short a global commodities boom.

Mobius has yet to announce any plans to retire or scale back his workload.