I looked at their terms and they qoute:
"For example, after reviewing partner statistics, we may convert partners that do not meet the 20-1 (unique click to sign up ratio) or 25-1 (signups to paying membership) from a CPC to a percentage payout without notification."
Note that they say we MAY convert partners.
And they also state that they'll pay $0.045 per unique if you convert better than 1:30 for free signups etc. it's a sliding scale per click program.
Anyway I think their terms suck, they blame everything on the webmasters and nothing on themselves...
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