# Reading instructions

Each message or component block is presented in a table.
Each table row is a message field or component block having the following characteristics:

| Tag characteristic: `Required`                                                                      | Description                                                                                                                                  |
| --------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------- |
| **yes**                                                                                             | Mandatory tag                                                                                                                                |
| **no**                                                                                              | Optional tag                                                                                                                                 |
| **yes, conditionally***                                                                             | Conditionally required tag. <br/>The condition is provided after `*` in the corresponding description.                                       |
| **yes, by Revolut FIX Gateway**                                                                     | Tag is required by Revolut FIX Gateway, but **not** required by the [FIX 4.4](https://www.onixs.biz/fix-dictionary/4.4/index.html/) standard |
| **yes, by [FIX 4.4](https://www.onixs.biz/fix-dictionary/4.4/index.html)**                          | Tag is **not** required by Revolut FIX Gateway, but required by the [FIX 4.4](https://www.onixs.biz/fix-dictionary/4.4/index.html) standard  |