Andy,
Being in stock markets for the last 15 years, I can say that stocks are speculative in nature (99% of the time). Remember Bluebird was just trading $17 last year, after the announcement of human trials the stock shooted to $181 in few months. The answer is speculation, Bluebird has not made any money from its technology, it is on trails basis but stock is trading $81 these days. It came down quickly because news about competition (SKMCC).
News, speculation, big whales at Bay street and Wall street manipulates money and gets bigger.
Note to others: I do not own Bluebird but watch the stock movement as we need this company to succeed.