Apple is one of the 'Four Giants' fueling the conglomerate's value, according to Warren Buffett in his annual letter.

 Warren Buffett said Apple is now one of the four pillars that drive Berkshire Hathaway, his conglomerate of mostly old-economy businesses that he's built over the last five decades.

Thanks to its chief executive, the 91-year-old investment legend included Apple under the heading "Our Four Giants" in his annual letter to shareholders, and even labeled the firm the second-most significant behind Berkshire's cluster of insurers.

"While Tim Cook, Apple's outstanding CEO, rightly sees Apple product users as his first love," the letter continued, "all of Tim's other constituencies benefit from Tim's managerial touch as well."

Cook's stock repurchase approach provides the conglomerate increasing ownership of each dollar of the iPhone maker's earnings without the investor having to lift a finger, according to the "Oracle of Omaha."

"Apple, our runner-up Giant in terms of year-end market value, is a different kind of investment. "Our stake here is just 5.55 percent, up from 5.39 percent a year ago," Buffett wrote in the letter. "That rise appears to be insignificant. However, consider that each 0.1 percent of Apple's earnings in 2021 is worth $100 million. We did not use any funds from Berkshire Hathaway to achieve our accretion. Apple's repurchases were successful."

Buffett's investing deputies Todd Combs and Ted Weschler influenced Berkshire to start buying Apple stock in 2016. By mid-2018, the conglomerate had acquired a 5 percent share in the iPhone maker for $36 billion. Apple's investment is now worth over $160 billion, accounting for 40% of Berkshire's equity holdings.

"It's critical to note that only Apple dividends are included in Berkshire's GAAP profit reports, and Apple paid us $785 million last year." Despite this, our share of Apple's profits was a whopping $5.6 billion. "We welcome the company's decision to repurchase Apple shares with a large portion of the money is kept," Buffett stated.

Outside of index and exchange-traded fund providers, Berkshire is Apple's largest shareholder. Over the years, the conglomerate has received monthly dividends from the computer giant, averaging around $775 million every year.

"It's critical to note that only Apple dividends are included in Berkshire's GAAP profit reports, and Apple paid us $785 million last year." Despite this, our share of Apple's profits was a whopping $5.6 billion. "We welcome the company's decision to repurchase Apple shares with a large portion of the money is kept," Buffett stated.

Outside of index and exchange-traded fund providers, Berkshire is Apple's largest shareholder. Over the years, the conglomerate has received monthly dividends from the computer giant, averaging around $775 million every year.