the average P/S ratio of the S&P 500 is at a historic high around 1.8 (http://www.multpl.com/s-p-500-price-to-sales) with long term average at 1.4, so this is still double the long term average. Square's gross margins are very thin in comparison to many other "household name" tech companies, so it deserves a much lower P/S. I've also heard growth is really slowing. This multiple doesn't surprise me at all, and I still won't be buying any of the stock.