Lee Kun-hee, front row right, then-chairman of Samsung Electronics, sits with his wife Hong Ra-hee, front row center, and their three children as they watch the men's 400-meter swimming final at the the 2012 London Olympics. Yonhap

Four family members of Korea's top conglomerate, Samsung, saw the value of their shares across the group's affiliates decline due to the weaker-than-expected quarterly earnings posted by the company, data showed Wednesday.

Ahead of the stock market opening, Tuesday, Samsung Electronics estimated its operating profit in the third quarter at 9.1 trillion won ($6.8 billion).

The amount was 12.8 percent down from three months earlier, and fell significantly short of Monday's brokerage consensus of 10.77 trillion won.

Data from corporate tracker FnGuide showed that the stocks owned by Samsung Electronics Chairman Lee Jae-yong, his mother Hong Ra-hee, and his two younger sisters, Lee Boo-jin and Lee Seo-hyun, were valued at a combined total of 29.88 trillion won after the market closed on Tuesday.

This was more than 20 percent down from the July 11 valuation placed at 38.8 trillion won, when Samsung Electronics recorded its annual high at 87,800 won per share on the local benchmark KOSPI.

The company finished at 60,300 won, Tuesday, retreating by 31.32 percent from the July 11 valuation.

"The Samsung family had more than one-fifth of their stock values plummeting in nearly three months due to Samsung Electronics' earnings," FnGuide said.

The four family members hold stakes in Samsung Electronics, Samsung C&T, Samsung SDS and Samsung Life Insurance, among other affiliates.

Samsung Electronics accounted for the 88.99-percent decline of their aggregate share values, FnGuide explained.

The value of shares held by Lee Jae-yong dropped from 16.86 trillion won to 13.58 trillion won.

Hong, the former director of the Samsung Museum of Art, also saw her shares decline in value from 8.85 trillion won to 6.15 trillion won.

The value of shares owned by Lee Boo-jin, CEO of Hotel Shilla, also dropped from 6.85 trillion won to 5.39 trillion won.

Meanwhile, Samsung C&T President Lee Seo-hyun's stocks fell to 4.75 trillion won, from 6.23 trillion won.

Still, Samsung chair Lee retained his top spot on the list of the country's wealthiest stockholders.

However, Hong, who previously ranked second, conceded to Meritz Financial Group Chairman Cho Jung-ho, coming in third on the list.

Lee Boo-jin and Lee Seo-hyun also saw their respective rankings fall by one spot to fourth and fifth place, respectively.

The shares owned by members of the family-controlled Samsung conglomerate have been subject to inheritance tax since the death of former Samsung Electronics Chairman Lee Kun-hee in October 2020.

The total inheritance tax amounted to 12 trillion won. The four family members have been paying inheritance taxes in installments for the assets inherited, in line with a five-year plan.

Industry sources are cautious over whether Samsung Electronics can rebound in the fourth quarter.

They attributed the chip giant's disappointing performance to lower demand for memory chips, due to contracting sales of smartphones and personal computers.

The company is also grappling with the high-bandwidth memory business that weighed heavily on its third-quarter earnings.

Samsung continues to vie for the product approval of U.S. artificial intelligence chip giant Nvidia. However, its cross-town rival SK hynix has already begun supplying its products to the U.S. firm.