David Rutter admits that the companies participating in R3 want to build blockchain applications to form a major part of banks' operating systems as many of those have obsolete legacy IT systems that were integrated during a wave of mergers in the late 1990s and early 2000s. The consortium's joint efforts have created a public blockchain called Corda, which is focused on dealing with the financial world in handling complex transactions and restricting access to transaction data. The aim of Corda is to provide a platform with common services to make sure that any services built on top of it are compatible with the IT systems of participants involved.