Warren Buffett has typically avoided tech stocks, but on Monday he made his biggest technology investment yet—and it wasn’t Apple or Google. Buffett’s Berkshire Hathaway invested $10.7 billion in IBM, taking a 5.4 percent stake in the company. The move made Berkshire Hathaway IBM’s second-biggest investor, and it paid immediate rewards, posting a 12 percent gain. Buffett went ahead with the acquisition even though IBM’s shares are trading near an all-time high; he says he’s not worried about a drop-off. The company, he told The Wall Street Journal, "fits all my principles … it's something we expect to own indefinitely."