It does not allow to trade on all the stocks listed on BSE and NSE. They will simply tell - "Our fund managers do not feel safe in trading the stocks of xxx company", hence we do not list and allow trading of such stock. What if I find some profit in buying a particular stock- but it does not allow me to trade on their portal.
This is called POKING THEIR NOSE or THRUSTING THEIR WASTE OPINIONS. Sometimes this really S#CKS. Friends - believe me - please do not open an account with ICICI direct.