[lvs]

Although there's no serious enforcement, having those three days be uncompensated has certain legal requirements under labor laws in the US and some other jurisdictions. In particular, it may be necessary to define the terminology during that trial period in a very specific way (e.g. a "trainee"... IANAL).

[imparvez]

That's quite interest to know. However I was going to limit myself till the introductions are made when there's a match. And leave them to discuss the terms. Like travel/stay/pay etc. Now that you've mentioned this I'll need to do some reading up. Thanks :)

[lvs]

For the US, you probably want to look into the US Supreme Court case Walling v. Portland Terminal. Generally speaking (again, IANAL), it sounds like the exemptions have to do with ensuring it's an educational experience that benefits the trainee more than the employer.

[kvprashant]

Communicating the terminology in advance is very important. But, do hackathons fall under these legal requirements? A group of people working for n days without compensation.