Funding Bitcoin development seems to have always been problematic.

While the Bitcoin industry collectively has raised more than a billion dollars worth of investment over the past years, development of the Free and Open Source Software the industry largely relies on has always had trouble gathering sufficient funds and manpower for development. Several arrangements to raise funds have been tried over the years – but with varying degrees of success and longevity.

Bitcoin Core, considered by many to be Bitcoin's "reference client," therefore, announced a "Sponsorship Programme" earlier this week. As the latest effort to raise funds, this program is intended to be an easy access-point for companies and other Bitcoin industry players to support Bitcoin Core developers and projects. Companies that decide to take part in the sponsorship program will join a, so-far, short list of entities that do already help fund Bitcoin Core development.

These are the main sources of funding as it currently stands:

MIT Media Lab's Digital Currency Initiative

Shortly after the effective bankruptcy of the Bitcoin Foundation a year ago, the three Bitcoin Core developers funded by this foundation – lead maintainer Wladimir van der Laan, former lead Gavin Andresen and Cory Fields – were hired by the then newly established MIT Media Lab's Digital Currency Initiative.