Quantum Computing (QC) is an emerging technology with a long development road for mass adoption. Nonetheless, there is excitement around the potential for QC to add business value. Through a literature review and interviews with key stakeholders currently using QC, informed by the literature, we conducted four case studies of major corporations adopting QC in various industries. The case studies show that companies are beginning to innovate with quantum computing, adding value to their current high-performance computing systems. The findings from the case studies illustrate and enrich the Diffusion of Innovations (DoI) theory as a framework for adopting and managing technological innovations, along with Crossing the Chasm as a follow-on to DoI. Specifically, the paper identifies the current adopters that have actively engaged in developing QC applications with other players and analyzes the four elements of innovation diffusion led by these innovators.