Startup Grooming: Take a Page from IBM's book
The rules for nose hair are inflexible and fixed: when it is protruding from your nostrils, it has to be cut. Period. There is no "fashionable length" for nose hair; you cannot develop your own signature nose hair style. A man who cannot manage his nose hairs is telling the world he cannot deliver venture capital-sized returns.
The same is true of the software you develop. You can't just let it hang out there without some definition and structure. From day 1, you must track and monitor all third party software that is being incorporated into product. Nothing kills your credibility with investors faster than being unable to demonstrate that you have chain of title to all of your product.
It's not so great from a customer perspective, either, when you have to delay launch because you are still negotiating a resale license from the supplier of that piece of trialware that your engineers threw in to the product.
To spot-audit your development work, take a page from IBM's book: have someone run a search for the letter “C” through your source code. Any copyright notices for third party software that turn up can then be traced and dealt with – either by scrubbing the third party materials from the code or ensuring you have the correct license for use in product.