I'll save you the read. A Google employee downloaded 100k documents from the company-wide available internal wiki, identified all the ones that seemed anywhere from highly-to-mildly offensive to anyone in the world, and then published it all as a book on Amazon. The book has been out for about a year and continues to sell well (not to mention the hundreds of paid media appearances for the author to speak in front of like-minded audiences).
Here's the fun part: Google considered suing, but recognized that this would trigger the Streisand Effect and let him off the hook. Obviously, this was a calculated risk this dude took and that paid off (at least from the legal perspective).
Did Google act ethically 100% of the time? God no! But did it hurt them to have everything out in the open? You betcha.
So clearly there's a market out there for juicy internal documents. I would still say the first step is not to do anything wrong, ever. But once you have enough people working for you and you can't be in every meeting at all times, shit is going to happen, and people are going to want to pay to find out about it.
EDIT: replaced "filtered out" with "identified"
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