I must admit, I don't even know about 90% of these companies. And quite interesting to see just how many companies operate in the same field. Perhaps some of you will find this interesting. http://cybersecurityventures.com/cybersecurity-500/
BTW, this is more of a list of companies to watch for the coming 5 to 10 years, not just for 2015. Another thing that I noticed is how many websites are quite badly designed, too heavy and sometimes there is just too much info, I would advise them to keep it simple. This website is really a joke when it comes to the look: https://www.paloaltonetworks.com/
Interesting stuff, in 2020 about 7 billion bucks will be spend on security software in Europe alone. No wonder so many companies are trying to get a piece of the pie. http://www.idc.com/getdoc.jsp?containerId=prEMEA41728316
Another interesting article, didn't know that Cylance and Lookout were that highly valued: https://www.cbinsights.com/blog/cybersecurity-startup-funding/