The Rubygems Partnership is a cooperative effort between Ruby Central and Ruby Together to ensure that RubyGems.org is funded, stable, maintained, and supported.
Ruby Central, organizers of the international RubyConf and RailsConf conferences, own the RubyGems.org service. They underwrite hosting costs and ensure that the service is able to continue long-term without needing any external source of funding.
Ruby Together provides funding and coordination for ongoing development, maintenance, and support work, as well as on-call system administrators. This ensures that the service continues to mature, grow, and improve, as well as ensuring that everything continues to run in tip-top shape.