The are two aspects in your questions: the mql source code and the strategy logic.

1. The source code of indicators, base mqh classes and exported expert advisors is Copyrighted and owned by Forex Software Ltd and distributed under the following rules:

//+--------------------------------------------------------------------+
//| Copyright:  (C) 2014 Forex Software Ltd.                           |
//| Website:    http://forexsb.com/                                    |
//| Support:    http://forexsb.com/forum/                              |
//| License:    Proprietary under the following circumstances:         |
//|                                                                    |
//| This code is a part of Forex Strategy Builder. It is free for      |
//| use as an integral part of Forex Strategy Builder.                 |
//| One can modify it in order to improve the code or to fit it for    |
//| personal use. This code or any part of it cannot be used in        |
//| other applications without a permission.                           |
//| The contact information cannot be changed.                         |
//|                                                                    |
//| NO LIABILITY FOR CONSEQUENTIAL DAMAGES                             |
//|                                                                    |
//| In no event shall the author be liable for any damages whatsoever  |
//| (including, without limitation, incidental, direct, indirect and   |
//| consequential damages, damages for loss of business profits,       |
//| business interruption, loss of business information, or other      |
//| pecuniary loss) arising out of the use or inability to use this    |
//| product, even if advised of the possibility of such damages.       |
//+--------------------------------------------------------------------+

It means that:
* You cannot Copy/Paste any part of this code and to create other application.
* You can modify the experts for your own needs and to use it as long as you want, but you cannot distribute the changed files.

2. The expert logic is not and cannot by copyrighted by anyone. This is a quotation from Circular 1 of US Copyright Office: Copyright Basics

It mains that I don't have claims on the indicator logic rules and parameters you use and to the structure, idea and logic of your strategy. You can do whatever you want with it.

All that means:

You can:
- trade with your experts as long as you want;
- publish, distribute, gives for free or sell the experts as you want but without changing the copyright and contact info;
- modify the code and use for your own needs;
- study the way the experts and indicators work and create other experts, indicators or programs without limitations;
- describe, explain, write articles, posts, books for the ideas and logic rules of the created experts without limitations;

You cannot:
- Change the contact and copyright info of the base mqh files and exported EAs;
- Use the files or part of the code for creating other indicators, experts or programs.

You can sell the produced experts without limitations. The compilation or protection of the expert is not a problem.
The license limits the rights of using our MQL code in third party software. For example an author of an EA Builder software cannot use our code in his app.