diff --git a/content/momentum/4/4-lua-summary-table.md b/content/momentum/4/4-lua-summary-table.md
index a427611f..cf5d4137 100644
--- a/content/momentum/4/4-lua-summary-table.md
+++ b/content/momentum/4/4-lua-summary-table.md
@@ -175,7 +175,7 @@ This section contains tables of Lua functions. Click the function name for detai
| [msys.validate.dk.get_responsible_domain](/momentum/4/lua/ref-msys-validate-dk-get-responsible-domain) – This function requires module "dk_validate". "msg" is a mail message. "ctx" is the validation context. It returns the responsible domain for the current message | msg, ctx | msys.validate.dk | 4.0 | data, data_spool, data_spool_each_rcpt |
| [msys.validate.dk.sign](/momentum/4/lua/ref-msys-validate-dk-sign) – Sign a message using a Domain Key | msg, ctx, options | msys.validate.dk | 4.0 | core_data_validation |
| [msys.validate.openarc.sign](/momentum/4/lua/ref-msys-validate-openarc-sign) – Sign a message using OpenARC | msg, options, [ar] | msys.validate.openarc | 5.0 | core_post_final_validation |
-| [msys.validate.openarc.verify](/momentum/4/lua/ref-msys-validate-openarc-verify) – Verify ARC sets | m | msys.validate.openarc | 5.0 | data_spool, data_spool_each_rcpt |
+| [msys.validate.openarc.verify](/momentum/4/lua/ref-msys-validate-openarc-verify) – Verify ARC sets | msg | msys.validate.openarc | 5.0 | data_spool, data_spool_each_rcpt |
| [msys.validate.opendkim.get_num_sigs](/momentum/4/lua/ref-msys-validate-opendkim-get-num-sigs) – Return the number of DKIM signatures | dkim | msys.validate.opendkim | 4.0 | data, data_spool, data_spool_each_rcpt |
| [msys.validate.opendkim.get_sig](/momentum/4/lua/ref-msys-validate-opendkim-get-sig) – Get a signature from a DKIM object | dkim, [num] | msys.validate.opendkim | 4.0 | data, data_spool, data_spool_each_rcpt |
| [msys.validate.opendkim.get_sig_canons](/momentum/4/lua/ref-msys-validate-opendkim-get-sig-canons) – Fetch the canonicalizers used for a DKIM signature | dkim_sig | msys.validate.opendkim | 4.0 | data, data_spool, data_spool_each_rcpt |
@@ -188,7 +188,7 @@ This section contains tables of Lua functions. Click the function name for detai
| [msys.validate.opendkim.get_sig_selector](/momentum/4/lua/ref-msys-validate-opendkim-get-sig-selector) – Fetch the selector associated with a DKIM signature | dkim_sig | msys.validate.opendkim | 4.0 | data, data_spool, data_spool_each_rcpt |
| [msys.validate.opendkim.get_sig_signalg](/momentum/4/lua/ref-msys-validate-opendkim-get-sig-signalg) – Return the signing algorithm as a string | dkim_sig | msys.validate.opendkim | 4.0 | data, data_spool, data_spool_each_rcpt |
| [msys.validate.opendkim.sign](/momentum/4/lua/ref-msys-validate-opendkim-sign) – Sign a message using OpenDKIM | msg, vctx, [options] | msys.validate.opendkim | 4.0 | core_final_validation |
-| [msys.validate.opendkim.verify](/momentum/4/lua/ref-msys-validate-opendkim-verify) – Verify an DKIM signature | m | msys.validate.opendkim | 4.0 | data, data_spool, data_spool_each_rcpt |
+| [msys.validate.opendkim.verify](/momentum/4/lua/ref-msys-validate-opendkim-verify) – Verify an DKIM signature | msg | msys.validate.opendkim | 4.0 | data, data_spool, data_spool_each_rcpt |
| [sess:request_add_header](/momentum/4/lua/ref-sess-request-add-header) – Set the header of an HTTP session | header, value, replace | msys.httpclnt | 4.0 | http_request_eval |
| [sess:request_delete_header](/momentum/4/lua/ref-sess-request-delete-header) – Delete a header from an HTTP session | header | msys.httpclnt | 4.0 | http_request_eval |
| [sess:request_finalize](/momentum/4/lua/ref-sess-request-finalize) – Finalize changes to an HTTP request | update | msys.httpclnt | 4.0 | http_request_eval |
diff --git a/content/momentum/4/hooks/core-post-final-validation.md b/content/momentum/4/hooks/core-post-final-validation.md
new file mode 100644
index 00000000..341271bd
--- /dev/null
+++ b/content/momentum/4/hooks/core-post-final-validation.md
@@ -0,0 +1,92 @@
+---
+lastUpdated: "11/26/2024"
+title: "post_final_validation"
+description: "hook invoked after the normal final validation"
+---
+
+
+## Name
+
+post_final_validation — This hook is invoked after the normal
+[final_validation](/momentum/3/3-api/hooks-core-final-validation) hook
+
+## Synopsis
+
+`#include "hooks/core/final_validation.h"`
+
+| `int **core_post_final_validation** (` | closure, | |
+| | msg, | |
+| | ac, | |
+| | ctx`)`; | |
+
+`void * closure`;
+`ec_message * msg`;
+`accept_construct * ac`;
+`validate_context * ctx`;
+
+
+## Description
+
+This hook is invoked right after the
+[final_validation](/momentum/3/3-api/hooks-core-final-validation) hook is called. Its return value
+does not have significance for now.
+This hook is added as the absolute last point before writing the message into spool.
+It guarantees that operations implemented in this hook will happen after the operations done in
+`final_validtion`.
+No any message modification expected after this stage.
+To avoid undefined race between multiple implementations of the same hook, you shall only have up
+to one implementation for this hook.
+It's the recommended hook point for ARC signing/sealing.
+
+
+**Parameters**
+
+The parameters from this hook are the same as the ones for `final_validation` hook.
+
+
+
+- closure
+
+-
+
+A pointer to the closure function.
+
+
+
+- msg
+
+-
+
+A pointer to an ec_message struct. For documentation of this data structure see [“ec_message”](/momentum/3/3-api/structs-ec-message)
+
+
+
+- ac
+
+-
+
+The `accept_construct` struct. For documentation of this data structure see [“accept_construct”](/momentum/3/3-api/structs-accept-construct)
+
+
+
+- ctx
+
+-
+
+The `validate_context` struct. For documentation of this data structure see [“validate_context”](/momentum/3/3-api/structs-validate-context)
+
+
+
+
+
+**Return Values**
+
+This hook returns `int`, but for now has no significance, i.e. the return value is not checked in
+the caller.
+
+**Threading**
+
+This hook will be called in any thread.
+
+
+
diff --git a/content/momentum/4/modules/openarc.md b/content/momentum/4/modules/openarc.md
index c8a65a11..de595665 100644
--- a/content/momentum/4/modules/openarc.md
+++ b/content/momentum/4/modules/openarc.md
@@ -36,6 +36,6 @@ The `msys.validate.opendarc.sign` does verification first. You should only invok
It's recommended to invoke `msys.validate.opendarc.verify` in `validate_data_spool` or
[`validate_data_spool_each_rcpt`](/momentum/3/3-api/hooks-core-validate-data-spool-each-rcpt) hook.
`msys.validate.opendarc.sign` shall be invoked in the last validation phase, in
-[`post_final_validation`](/momentum/4/hooks/core-post-final-validate) hook.
+[`post_final_validation`](/momentum/4/hooks/core-post-final-validation) hook.
See API examples for hook usages.
diff --git a/content/momentum/4/modules/summary-all-modules.md b/content/momentum/4/modules/summary-all-modules.md
index cd19e8d1..71b58707 100644
--- a/content/momentum/4/modules/summary-all-modules.md
+++ b/content/momentum/4/modules/summary-all-modules.md
@@ -70,7 +70,7 @@ All modules are listed alphabetically with a brief description. Singleton module
| [msgc_client](/momentum/4/modules/msgc) (*singleton*) | 4.0 | The client component of MSGC | | ✓ | | |
| [msgc_server](/momentum/4/modules/msgc) (*singleton*) | 4.0 | The server component of MSGC | | ✓ | | |
| [“mxip - IP Addresses In MX Records”](/momentum/4/modules/mxip) | 4.2 | Enable Momentum to deliver to domains with a textual IP address | | | | |
-| [“opendarc – Open Source ARC”](/momentum/4/modules/opendarc) | 5.0 | Validate/sign mail using ARC | | | ✓ | |
+| [“openarc – Open Source ARC”](/momentum/4/modules/openarc) | 5.0 | Validate/sign mail using ARC | | | ✓ | |
| [“opendkim – Open Source DKIM”](/momentum/4/modules/opendkim) | 4.0 | Validate/sign mail using DKIM signatures | | | ✓ | |
| [“outbound_audit – Outbound traffic analytics”](/momentum/4/modules/outbound-audit) | 4.0 | Provides time-series analytics on the behavior of receiving domains | | ✓ | | |
| [“outbound_smtp_auth”](/momentum/4/modules/outbound-smtp-auth) | 4.2 | Enables users to specify authentication parameters for a given set of messages | | | | |