MetaTrader 5 is growing fast. More brokers are migrating to MT5, more traders are using it, and more EA developers are building for it. If you have built or are building an MT5 Expert Advisor you plan to sell, protecting it from piracy is essential before you distribute a single copy.
This guide covers every available method for MT5 EA copy protection, ranked by effectiveness, and explains what combination works best for serious EA sellers.
The fundamentals are the same, but there are a few differences to be aware of. MT5 compiles to .ex5 files instead of .mq5 source. MetaQuotes has improved the obfuscation of compiled .ex5 files compared to older .ex4 files, making them marginally harder to decompile. However, determined crackers still find ways around this, so you should not rely on compilation alone.
The good news: a server-side license validation system works identically on MT5 as on MT4. Your EA makes an HTTPS call to the license server using WebRequest, the server validates the key and account number, and the EA either runs or shuts down.
Your EA calls an external license server on startup. The server validates the license key against the customer account number and returns an authorization. Since all validation logic lives on the server, there is nothing in the EA file to reverse-engineer. Combined with account binding, this is the gold standard for EA protection.
Link each license to a specific MT5 account number. Even if a customer shares their license key, it will only work on the account it was issued for. Every unauthorized use attempt is logged on the server. This eliminates the most common piracy scenario: customers sharing keys in group chats.
Never distribute the .mq5 source file. Always compile to .ex5 before distribution. While compiled files can theoretically be decompiled, this raises the bar significantly. Anyone willing to put in the effort to decompile your EA was never going to pay for it anyway.
Time-limited licenses automatically expire. Even if a license key is leaked, it stops working after the subscription period. For monthly subscription EAs, this means any leaked key becomes useless within 30 days. Combine with server-side validation for full control.
Storing a list of allowed account numbers inside the EA file provides minimal protection. This can be bypassed by anyone with basic reverse engineering skills. Avoid this as your primary protection method.
Some developers manually obfuscate their MQL5 code before compiling, renaming variables and adding confusing logic. This makes decompiled code harder to read but provides no actual security. A motivated attacker will still find the core logic.
To add server-side license validation to your MT5 EA, you need three things:
The WebRequest function in MQL5 allows your EA to make HTTP calls to external servers. This is the mechanism that enables server-side validation. Your code sends the license key and account number, and the server returns a JSON response with the authorization result.
Let us be specific about what piracy looks like for an MT5 EA seller:
With server-side license validation and account binding, step 2 fails. Customer A's .ex5 file works on their account. It fails on every other account. The Telegram group gets an error message. The spread stops immediately.
Set license expiry to match your billing cycle. When a customer's subscription lapses, the license automatically becomes invalid. The EA shuts down on their next startup. No manual intervention required.
Issue a permanent license bound to the customer's account number. If they want to run the EA on a second account, they purchase an additional license. This creates a natural upsell without any extra sales effort.
Issue a time-limited trial license (7 or 14 days) that automatically expires. When the trial ends, the customer must purchase a full license. This is much more effective than sharing an unprotected trial version.
MTLicense was built specifically for MetaTrader EA developers. It supports MT5 natively, handles all the server infrastructure, and provides a simple MQL5 integration library. You register your EA, configure your license terms, and issue keys through a clean dashboard. The integration on the EA side is under 50 lines of MQL5 code.
Every license is automatically bound to the account number the customer specifies during activation. Expiry is handled server-side with no action required from you. Failed validation attempts are logged so you can monitor for abuse.
Full MT5 copy protection with account binding, expiry management, and a developer dashboard.
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