According to people familiar with the matter, Softbank Corp.The group quietly amassed a $5 billion stake in Roche, betting on the pharmaceutical company's strategy of using data to develop drugs.

The Japanese conglomerate is now one of Roche's biggest investors, according to compiled data.

Roche's sales have recently been boosted by its Covid-19 testing business. The company's diagnostic department responded quickly to the coronavirus outbreak, but life was even harder for the pharmaceutical sector as older cancer drugs faced increasing competition.

Shares of the Basel, Switzerland-based company are up 8.8% over the past 12 months. The MSCI global pharmaceutical, biotechnology and life sciences index is up 14.7%.