Financing open source using tax breaks on donations made to endowment funds or general interest associations is a construct available in France and a viable alternative to R&D expenditures for sponsoring open source projects. We will present several initiatives from the Libre Endowment Fund ("Fonds de Dotation du Libre" in French) - from financing feature development of open source software to releasing a 4G/5G base station as open source hardware or supporting litigation against the French government's decision to host Health Data on Microsoft servers. The recently published FOSS contributor report showed that 48.7% of contributors were paid for their contributions by their employer with only 2.95% being paid by a third party. So even today as (open source) software continues to eat the world, almost half of all projects lack the financial base for ensuring their respective software's long-term existence. To finance the long term maintenance of its open source software stack, Nexedi has created the Libre Endowment Fund ("Fonds de Dotation du Libre" or FDL in French). It is a French endowment fund which complies with strict auditing procedures. With this status, French Law permits corporations and individuals to donate to the FDL and claim back up to 60% from future income taxes (65% for individuals). Rather than investing directly in the maintenance or continuous development of own or third party solutions, Nexedi and other companies (ex. Amarisoft) can pool donations which then support the maintenance or development of open source software, open source hardware or open services. FDL also benefits from a scientific board of advisors which include three developers of open source software (Jean-Paul Smets, Stéfane Fermigier, Gaël Varoquaux) who also hold a PhD in computer science or mathematics. This scientific board follows the same procedures as governement sponsored RTD projects and thus also contributes to the juridical safety of FDL.