Related: requiring some kind of insurance that pays out when a certificate becomes net-negative.
Suppose we somehow have accurate positive and negative valuations of certificates. We can have insurers sell put options on certificates, and be required to maintain that their portfolio has positive overall impact. (So an insurer needs to buy certificates of positive impact to offset negative impact they've taken on.)
Ultimately what's at stake for the insurer is probably some collateral they've put down, so it's a similar proposal.
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