The New York-based operator of a major mutual fund has hinted it believes blockchain technology could be a threat to credit card network operators.

The comments came as part of Ruane, Cunniff & Goldfarb’s annual report on the performance of the Sequoia Fund, the firm’s consolidated portfolio offering. The Sequoia Fund currently holds stock in 10 publicly traded companies as part of its portfolio, with MasterCard accounting for 4.3% of its assets.

In the report, Sequoia praised MasterCard for its strong performance since its 2006 IPO, but indicated that it believes new technologies, including blockchain, will begin to affect the company’s value.

Sequoia wrote:

“MasterCard’s virtues are well-appreciated by the stock market but the evolution of mobile payment habits and the rise of blockchain ledger technology could pose longer term challenges to the company’s wildly profitable business model.”

The fund has a storied track record among investors, returning three times more than the S&P 500 during its more successful runs.

In addition to MasterCard, other Sequoia Capital portfolio holdings include Berkshire Hathaway, O’Reilly Automotive and Alphabet, Google’s parent firm.

Correction: An earlier version of this article mentioned Sequoia Capital, a VC firm that is not connected to Sequoia Fund.

MasterCard image via Shutterstock