Technical Clarification Request – MetaTrader 5 Computer ID (CID) and Device Identification

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Dear MetaQuotes Technical Support Team,

I am contacting you to request technical clarification regarding the Computer ID (CID) recorded by MetaTrader 5 trading servers.

A trading firm has identified identical CID values across accounts belonging to different customer profiles. I have been informed that these matches conclusively establish access from the same physical device.

As I have only used my own personal computers and mobile phone, I would greatly appreciate clarification directly from the developers of MetaTrader 5.

In particular, could you please clarify the following:

  1. Is the Computer ID (CID) recorded by an MT5 server a guaranteed unique identifier of a physical device?

  2. Is it technically possible for two independent computers to generate the same CID without sharing hardware, software installations or account credentials?

  3. Which categories of information contribute to the CID? For example, hardware identifiers, Windows configuration, installation paths or operating system information. I am not requesting proprietary source code.

  4. Can a CID change following a MetaTrader update, Windows update, operating system reinstallation, hardware replacement or migration to another computer?

  5. Does the MT5 desktop application use a different identification mechanism from the Android and iOS applications?

  6. Can third-party services or server-side integrations cause the same CID to appear across multiple trading accounts?

  7. Does a matching CID alone conclusively establish that two accounts were accessed from the same physical device, or should additional information such as IP addresses, timestamps and client types be examined?

  8. Is there an official method for a trader to retrieve or verify the CID associated with their own MT5 installation?

I understand that certain implementation details may be proprietary. Even a general technical clarification regarding the reliability and limitations of CID-based device identification would be extremely helpful.

My intention is simply to understand the technical facts and ensure that the information is interpreted correctly.

Thank you very much for your time and assistance.

Kind regards,

Mario Guarracino

MARIOGUARRACINO:

Dear MetaQuotes Technical Support Team,

I am contacting you to request technical clarification regarding the Computer ID (CID) recorded by MetaTrader 5 trading servers.

A trading firm has identified identical CID values across accounts belonging to different customer profiles. I have been informed that these matches conclusively establish access from the same physical device.

As I have only used my own personal computers and mobile phone, I would greatly appreciate clarification directly from the developers of MetaTrader 5.

In particular, could you please clarify the following:

  1. Is the Computer ID (CID) recorded by an MT5 server a guaranteed unique identifier of a physical device?

  2. Is it technically possible for two independent computers to generate the same CID without sharing hardware, software installations or account credentials?

  3. Which categories of information contribute to the CID? For example, hardware identifiers, Windows configuration, installation paths or operating system information. I am not requesting proprietary source code.

  4. Can a CID change following a MetaTrader update, Windows update, operating system reinstallation, hardware replacement or migration to another computer?

  5. Does the MT5 desktop application use a different identification mechanism from the Android and iOS applications?

  6. Can third-party services or server-side integrations cause the same CID to appear across multiple trading accounts?

  7. Does a matching CID alone conclusively establish that two accounts were accessed from the same physical device, or should additional information such as IP addresses, timestamps and client types be examined?

  8. Is there an official method for a trader to retrieve or verify the CID associated with their own MT5 installation?

I understand that certain implementation details may be proprietary. Even a general technical clarification regarding the reliability and limitations of CID-based device identification would be extremely helpful.

My intention is simply to understand the technical facts and ensure that the information is interpreted correctly.

Thank you very much for your time and assistance.

Kind regards,

Mario Guarracino

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