Family members of Walter Scott Jr., a longtime Berkshire Hathaway Inc. director and friend of Warren Buffett who died last year, have retained his roughly 8% stake in Berkshire Hathaway Energy, according to a regulatory filing. 

That position is worth about $7.5 billion, based on Bloomberg calculations and details of an earlier filing showing that the stake in the Berkshire unit can be exchanged for shares in the parent company. 

The family members have agreed not to sell their shares in the energy subsidiary without offering Berkshire the right to buy them first, according to the filing. 

Scott had four children with his first wife, Carolyn, who died in 1983. His second wife, the former Suzanne Marshall, died in 2013. 

Scott died in September at age 90 and had a net worth of more than $6 billion at the time, according to the Bloomberg Billionaires Index. In 2010 he signed the Giving Pledge, an effort by Buffett and Microsoft Corp. co-founder Bill Gates to get the world’s richest to donate the majority of their wealth.

Scott said in his Giving Pledge letter to Buffett that “upon my death, virtually all of my remaining estate will go into” what’s now known as the the Suzanne and Walter Scott Foundation. 

This article was provided by Bloomberg News.