There are not too many graphene players or at least serious ones. Only a handful of publically traded companies on second-tier stock exchanges. No graphene companies are listed on the major stock exchanges, like NASDAQ, to the best of my knowledge.Only a few companies have any revenue (Graphene 3D is one of them). But there are a lot of wannabe companies that have neither revenue no big developments.
Graphene market is just forming $0.5B is not a huge number. The rate of growth is fast, though.
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