"It seems like a fad, and as a professional investor, it's not what we do," said David Dunn, president of Kingsbridge Wealth Management, who first bought bitcoin in 2014 and has invested in blockchain-related companies. "I'd rather invest in the companies using the technology themselves. The speculators might end up being right, and this becomes a solid investment because of the power of the technology, but we're not at that stage."