It certainly is, AFAIK.
It's my understanding that it "works" like this:
1) People doing better than some target are given credit for that.
2) These credits have value and can be sold to those doing worse than the target help them...
Of course, a lot of ordinary people might well be eligible for credits, so people in some region might mostly sell their credits to the few big businesses who are NOT meeting the target. In this case, the intent of the program has been thwarted: the body imposing the target has done a bunch of work to classify people and businesses, and make credits a new part of the economy, BUT those NOT in compliance might well be able to buy enough credits so as to cover their obligation and yet do nothing to mitigate the actual problem which triggered the legislation/regulation.
So, if a region already has an average compliance which is better than the target, the sources of non-compliance can just buy their way out of what they ought to do, take this as a cost of doing business, and never fix the problem(s) at issue.
