> does not contain any third-party software, including without limitation, “open source,” “copy left,” “public” or other similar code or anything derived from or based on any of the foregoing (unless approved by Gigster in writing)

So is a Gigster developer contractually obligated to build everything from zero and take advantage of no OSS whatsoever? This seems like asking to handcuff your developers into writing terrible software by reinventing the wheel.

Or do they have some additional "in-writing" approval document that specifies acceptable OSS licenses? Several companies I've worked for had lists of OSS licenses that were reviewed and approved by general counsel as acceptable (pretty much the list boiled down to BSD, MIT, Apache).

Then again it seems like if that were the case, the sensible approach would be to write the contract such that using open source software is acceptable, so long as it is offered under a license that appears on an approved list and does not obligate the release of the entire project's source code.