There should facility to group all the holding in demat and positional in various groups.

A group will be the collection of above said stocks marked by the user.

In Each group could be a trailing stop loss based on % or points can be place. The said trailing stop loss will be applicable on each all the stocks within the group.

This will help a great deal wherever the holding are in high number.

e.g.

holdings have 50 stocks

user divides them in 6 groups

And each particular group is assigned the trailing stop loss, so if any/all the stocks breaches the level the stop loss gets triggered only in those stocks.

The instruction placement is at group level however, transaction gets triggered on the volatility of each individual stock.