DBS would have these conditions to protect their content and users from abuse in some forms.
internal copyright of your work is subjective by your country and use of the copyright trademarks within your readme etc..
international copyright is pretty vague at best but most arguments are won or lost depending who registered it first via their countries methods.
The way I see it, If you slap up some code then by all means its public domain, If you posted a snippet with instructions for usage,Not everyone will follow the rules and some will still rip it apart for their own project.
Its best to assume any code you post will go through layers of user moral filters.