Talk about an eventful year: The Detroit-based parent company of Rocket Mortgage went public last August, while a surge in pandemic-driven demand for home mortgages more than tripled the company’s net revenue, to $15.7 billion. All 24,000 Rocket employees received shares at the IPO; as of late March, the stock was trading at 33% above the offering price. As staff transitioned to working from home, Rocket spent $14.5 million to supply them with tech and telecom equipment. (One reward for this employee-centric thinking: Rocket rose from No. 29 to No. 5 on this list.) The company gave back to its hometown, too: Rocket helped Detroit build, staff, and handle scheduling for a COVID mass-testing site, while its philanthropic arm bought machinery that makes masks and other PPE for local health care providers.