Offering the chance to win in exchange for user data

I don’t have comprehensive knowledge about the relevant US legislation but have worked in marketing departments within global organizations and running the sorts of campaign you are describing usually made our legal department a bit nervous. Here are a few pointers I can think of:
- Are you announcing this campaign online? If so it will reach people outside of the US so make sure you have terms and conditions specifying who is eligible to enter and if it is open to entrants in other territories, you will need to abide with their laws.
- Be careful about the additional data you want to collect (friends’ emails), perhaps better to let the original person invite their friends. You should only have people on your newsletter mailing list who have Opted In, you should not be adding them to your database without their permission.
- Be clear about the prize draw – is it a game of chance (sweepstake) or a competition (answering the right answers), generally – you should not be combining the two and be explicit in your T&Cs. For instance, collect the email but answering the questions is optional and doesn’t affect the participants’ chances of winning.
- Make sure the terms and conditions can be accessed on your website and you tell participants where to find them. e.g. provide a link to the document. This is usually mandatory legal requirement. Include details of how many prizes are available and when the draw will happen.
The safe way to go is to keep your campaign simple – if it is complicated to explain and there are many scenarios possible, it probably means you will fall foul.
If you think you will use these sorts campaigns often, it may be worth paying to get standard T&Cs drawn up and you can update the non-legal sections e.g. dates, prizes whenever you run the campaign. It will be worth thinking about all the scenarios in advance and the type of information you want to collect so that you use your lawyer’s time well.