Amazon may have posted Street-beating fourth quarter earnings this week, yet the company's stock remains way overvalued, said Jeremy Josse, Author of 'Dinosaur Derivatives and Other Trades'. Josse added that Amazon never delivers consistent earnings and is always spending huge sums on new projects in order to push off a true day of reckoning. Similarly, he is skeptical of Twitter's valuation, as well as its business model which he calls 'unproven.' Finally, Josse is wary of LendingClub's shares, saying the company trades at a massive multiple despite being a very traditional loan broker.