At my current workplace, on a particular project we have not been allowed to use third party libraries, due to fears of licensing issues if and when we come to sell the product. The project is predominantly for the business, but it would be nice if we could convert the product into something we could market.
Despite multiple discussions and suggesting to management that open source software licensed under an MIT or BSD license would not have any implications, they would not have it. This has meant writing pretty much everything we need from scratch.
The next task is to go about documenting the best way to include and use the tool kit in our application, will write about it if I get chance.