A funny thing happened in the stock market this week: Little-known company CYNK Technology (NASDAQOTH:CYNK) ran up to a high of $21 per share, an enormous gain from its $0.06 per share price in June. And then the SEC halted trading of the stock until July 25 at the earliest.

Why? It's unclear that a real business exists behind the ticker. With only one employee on record, and a $1.5 million loss on the books last year, CYNK Technology certainly doesn't seem to have earned its $5 billion valuation at yesterday's peak. Stock Advisor analyst Sara Hov and Rule Breakers analyst Simon Erickson talk about what powered such a huge run-up, and the biggest takeaway for investors from this story.