Which banks are using FIS?

I'm curious to know, which banks exactly are utilizing FIS, the Financial Information Services platform? Are these predominantly large multinational banks, or are smaller, regional banks also adopting this technology? Are there any specific industries or regions where FIS usage is more prevalent? What are the primary benefits that these banks are seeking to achieve by partnering with FIS? I'd love to get a clearer picture of the adoption rate and the driving factors behind its usage in the banking sector.