When I make reference to Buffett's favorite stock, I'm talking about none other than Berkshire Hathaway itself. Buffett has authorized the repurchase of $77.8 billion worth of Berkshire stock since 2018, which is more than twice the amount the conglomerate invested in Apple.

The Oracle of Omaha has more than enough justification to add to the roughly $78 billion he's spent buying shares of his favorite stock since mid-July 2018.

Investors can often benefit from following the recent movements and decisions made by the biggest names in the market, especially if they can work through reverse engineering some of the reasoning behind these decisions.

Buffett first invested in Verisign ( VRSN -0.27%) in 2012, and at the time of this writing, the shares have gone on to increase by at least 325% since then. He continued to buy shares in 2013 and 2014, but it has been more than 10 years since he added to the position. Here's why he's coming back to Verisign now.