Sales growth could accelerate now that it provides lower-cost, weight-management drugs. If you'd like to become a billionaire, paying attention to how other billionaires invest is a sensible way to get started. Everyday investors can easily keep tabs on billionaire stock purchases because the U.S. Securities and Exchange Commission (SEC) makes them disclose their trading activity every three months. In the latest round of disclosures, it's clear that a handful of funds run by billionaire investors bought sh ...