[mchahn]

> I thought the GPL says you have to provide the source code if your customer wants it.

There is nothing about what the customer wants. You have to either publish the source or provide a link, like a URL, to it.

[hias]

No, you don't have to publish the source code in public. You have to submit source code with your product to the customer, or a hint that the customer can request the source code if he wants to. This can be public, but it doesn't have to be public.