US-based investment management firm BlackRock has become the third-largest shareholder of South Korean brokerage house Samsung Securities, a filing showed Thursday.

BlackRock’s 12 affiliated entities hold a total of 5.46 percent stake (4.87 million shares) in Samsung Securities as of Feb. 28, according to a disclosure filed with the Financial Supervisory Service.

A minority shareholder with at least 5 percent of shares in a company is subject to filing obligations as a block holder of the company, under the current law.

Samsung Life Insurance is the largest shareholder of Samsung Securities with a 29.62 percent share, followed by the National Pension Service, whose share is about 10 percent.

According to BlackRock's annual report, as of last year the US company held only 3,645 shares of Samsung Securities through the iShares Emerging Markets Equity Index Fund.

This means the company recently increased its stake significantly in the Korean brokerage firm.

"Since (Samsung Securities) is a top-tier stable risk manager in the industry with revenue generation capabilities, it would have appealed to foreign investors," a Samsung Securities official said.

Samsung Securities has been consistently maintaining more than a 4 percent dividend yield. The dividend payout ratio also has been over 35 percent.

Among major domestic securities firms, Samsung Securities also became the only company with a global asset manager holding more than a 5 percent stake.