Frank Totonto, while in premise you have a good idea, not having nics in the dev pcs is litterally impossible. There is a live sourcecode repository that needs to be available via a lan, else you could not have multiple people develop the software. But, there are different routes that could be taken. For example, no network monitoring, as well as a fully open outbound internet connection was part of the issue. Physically segmenting the dev PCs from the internet is also something that should be looked at. Relatively speaking, this sounds like a network setup by a someone not versed in securtiy aspects, and it sounds like there were no policies-procedures to prevent this.