The challenge is getting the companies to (from their perspective) "share" the trust information with the world, which includes their competitors. I suspect we

The challenge is getting the companies to (from their perspective) "share" the trust information with the world, which includes their competitors. I suspect we might need a "taxonomy of trust" so to speak, that allows the trust data to be anonymized and aggregated into commonly-accepted meanings of trust contexts, trust roles, trust relationships, etc. That might let these companies to release the trust data into such a format through a blockchain perhaps, and be able to participate in consuming the aggregated data. I'd need someone well-versed in game theory to figure out if an advantage is conferred to "leeches"; a company in such a scenario who only consumes the aggregated data but never send into the blockchain what they accumulate on their own customers. I think that's a real danger with such a scheme, but am not sure how to strongly dissuade that behavior.