Bill Ackman of Pershing Square Capital Management and Andreas Halvorsen of Viking Global Investors are two billionaires worth following for investment ideas. They are entrusted with billions in assets to manage for clients, and that reflects a career of making smart investment choices.

At the moment, artificial intelligence (AI) looks like it will continue to be a dominant theme across the market in 2025, so you might want to start by looking at companies that compete in that arena.

The AI-driven software company has several key qualities that ... your way into your full position. Using this method to buy stocks is even more important for stocks that have recently run-up big and could pull back soon because of profit-taking.