Consult a lawyer if this concerns anything important, but I know at least elance has standard terms that all IP belongs to the person who hired the contractor.
You would want to check they're not using code they don't own, of course. The agreements bans it without disclosure, but in practice I'm sure many elance contractors use GNU code without mentioning it.
https://www.elance.com/q/sites/default/files/page_pdf/legal/...
You would want to check they're not using code they don't own, of course. The agreements bans it without disclosure, but in practice I'm sure many elance contractors use GNU code without mentioning it.