Stirling PDF

Details

The project is provided under a license which is MIT based but with certain content provided under a non-FOSS Stirling PDF User License which sets limits on use, modification & distribution.

From a quick review of the code, the FOSS code does not appear to rely on the non-FOSS code, and there are build flags to control the use of the non-FOSS code. The non-FOSS code appears to be for their pro & enterprise offerings.

The project advertises itself generally as “Open Source” on its website, including a couple of mentions on the homepage, and in its documentation. The documentation specifically appears to advertise non-FOSS features within the same section.

Following the downloads, it’s not clear which version of the software is provided, as there is little guidance via the distribution options, but it’s likely to be versions built to include the non-FOSS code since their guidance shows upgrading to “Pro” is done via just configuration changes, instead of via separate distributions.

The project appears to have received $2m in funding from Open Core Ventures, a venture capital firm which the project has partnered with. The project also appears to gain revenue from selling its “Pro” and “Enterprise” offerings which provide extra features and services for the software.