Alphabet, the parent company of internet giant Google, surpassed Apple as the world's most valuable company Monday, when investors snapped up stock after the company reported fourth-quarter earnings of nearly 5 billion dollars, according to dpa. The net earnings - 4.9 billion dollars to be precise - were an increase from 4.7 billion the year before. Revenue rose 18 per cent year-on-year to 21.3 billion dollars. The news beat analyst expectations and sent the company's shares skyrocketing. In after-hours trading, Alphabet shares shot up as much as 8 per cent, boosting the company's market value as high as 570 billion dollars, rivalling Apple's current value of 533 billion. Outside of market hours, the values are unofficial - but are an indicator Alphabet could take Apple's crown when trading begins Tuesday. Google formed Alphabet in August 2015 to house Google and its other companies, including side projects from space exploration to self-driving cars. But the search engine still represents by far most of the company's earnings. Advertising revenues for Google and its YouTube, Gmail and Android subsidiaries rose 17 per cent year on year to 19 billion dollars, while the side projects, which the company calls Other Bets, lost more than 3.5 billion dollars.