I have a friend interested in submitting footage to a range of Microstock sites. I'd like to give my friend a referral code in order that I might benefit financially from sales of her footage as I've given her lots of guidance and advice thus far. Can anyone tell me which sites offer referral codes when introducing new video contributors?

Thanks.

if i recall, Shutterstock you have to send an invite to gain that referral. dreamstime, i think the new member has just to give your id#. lastly, the latter referral is not forever, it is limited to 3 years.
and if your referral becomes exclusive later on, i think they end your referral. at least that's what happened to all my referrals.
like most sites, there will always be one form and another to cap what they pay you  ie as soon as they don't need you, they throw you out like one used to do in the dark ages with the piss collected overnight the spittoon  before shouting to the passersby "regarde leau"