VeriSign is ranked 5th in the S&P 500 for the highest profit margin, at about 56%, tied with Nvidia, according to third-quarter financial data.

Warren Buffett’s Berkshire Hathaway Inc. has been busy over the past week buying stock in an internet domain-name registry company, to extend its stature as the company’s largest shareholder.

Warren Buffett has invested more than $74 million in a Reston company best known for controlling internet domains for organizations across the globe.