IMS Health and investors including TPG Capital raised $1.3 billion after selling the stock for $20.  IMS Health Holdings Inc. shares gained 15 percent to $23.

The IPO marks a return for IMS to the public markets after it was acquired by a group of private-equity funds four years ago. While private, IMS spent $900 million on acquisitions between 2011 and 2013, and shifted its employee mix to become more client-facing.

IMS gathers data including on how drugs are marketed and prescribed and sells that along with analytical tools and services to clients including drugmakers, pharmacies and government agencies. Sales rose 4 percent to $2.54 billion last year, according to the filings. IMS says it competes with companies ranging from management consultancy Accenture Plc to Indian software developer Infosys Ltd.

According to Bloomberg News health-care spending in the U.S. is estimated to grow at an average rate of 5.8 percent through 2022, one percentage point more than the projected growth in gross domestic product, according to the Centers for Medicare & Medicaid Services. The Patient Protection and Affordable Care Act of 2010, which concluded its sign-up period this week, has brought into focus the various technologies that could help reduce these costs.

IMS’s owners — TPG, Canada Pension Plan Investment Board and Leonard Green & Partners LP — stand to begin exiting the four-year-old investment with a 160 percent profit at the offering’s midpoint, regulatory filings indicate. Because they’re not selling the entire holding in the IPO, that gain will be largely unrealized.