Berkshire Hathaway (NYSE:BRKa), led by CEO Warren Buffett, has shown significant interest in tech giant Apple (NASDAQ:AAPL) and its own company shares, according to the latest 13F filings and comments from the annual shareholder meeting. As of Monday this week, Apple reportedly accounted for 45.4% of Berkshire Hathaway’s $354 billion investment portfolio, making it the clear top investment.

According to Buffett, there are four primary reasons why Apple is highly valued by his firm. First, Apple’s brand recognition and customer loyalty are seen as key assets. Second, the company’s innovative nature and consistent updates to its products are appreciated by Buffett and his team. Third, Buffett expresses complete trust in Apple’s management team and its shift towards a platform business model with more emphasis on subscription services. Finally, Buffett appreciates Apple’s substantial capital-return program, which includes one of the largest nominal-dollar dividend payouts among public companies and a stock repurchase program that has bought back approximately $600 billion worth of its common stock since 2013.

However, another stock that has caught the eye of Warren Buffett is none other than Berkshire Hathaway itself. A change in policy on July 17, 2018, allowed Buffett and executive vice chairman Charlie Munger more freedom to buy back their company’s stock as long as they maintain at least $30 billion in cash, cash equivalents, and U.S. Treasuries on their balance sheet. Since this policy change, Berkshire Hathaway has consistently bought back its own shares for 20 consecutive quarters, totaling over $71 billion. This buyback program is viewed as a way to reward long-term investors by incrementally increasing their ownership stakes.

Furthermore, the buyback program has had a positive impact on Berkshire Hathaway’s earnings per share (EPS), which should rise as the outstanding share count declines for businesses with steady or growing net income.