diff --git a/src/docs/user/userguide/events.diviner b/src/docs/user/userguide/events.diviner
index b70b0fad42..7c3e79b8dc 100644
--- a/src/docs/user/userguide/events.diviner
+++ b/src/docs/user/userguide/events.diviner
@@ -182,16 +182,6 @@ edit. Data available on this event:
 This is similar to the previous event (will edit task) but occurs after the
 edit completes.
 
-== Differential: Will Send Mail ==
-
-The constant for this event is
-`PhabricatorEventType::TYPE_DIFFERENTIAL_WILLSENDMAIL`
-
-This event is dispatched before Differential sends an email, and allows you to
-edit the message that will be sent.  Data available on this event:
-
-  - ##mail## The @{class:PhabricatorMetaMTAMail} being edited.
-
 == Differential: Will Mark Generated ==
 
 The constant for this event is
@@ -204,34 +194,6 @@ doesn't need to be reviewed) or not.  Data available on this event:
   - ##is_generated## Boolean indicating if this file should be treated as
     generated.
 
-== Differential: Will Edit Revision ==
-
-The constant for this event is
-`PhabricatorEventType::TYPE_DIFFERENTIAL_WILLEDITREVISION`.
-
-This event is dispatched before a revision is edited, and allows you to
-respond to or alter the edit. Data available on this event:
-
-  - ##revision## The @{class:DifferentialRevision} being edited.
-  - ##new## A boolean indicating if this revision is being created.
-
-This is similar to the next event (did edit revision) but occurs before the edit
-begins.
-
-== Differential: Did Edit Revision ==
-
-The constant for this event is
-`PhabricatorEventType::TYPE_DIFFERENTIAL_DIDEDITREVISION`.
-
-This event is dispatched after a revision is edited, and allows you to
-react to the edit. Data available on this event:
-
-  - ##revision## The @{class:DifferentialRevision} being edited.
-  - ##new## A boolean indicating if this revision is being created.
-
-This is similar to the previous event (will edit revision) but occurs after the
-edit completes.
-
 == Diffusion: Did Discover Commit ==
 
 The constant for this event is
diff --git a/src/infrastructure/events/constant/PhabricatorEventType.php b/src/infrastructure/events/constant/PhabricatorEventType.php
index 49ff1fdef2..780d894a4b 100644
--- a/src/infrastructure/events/constant/PhabricatorEventType.php
+++ b/src/infrastructure/events/constant/PhabricatorEventType.php
@@ -13,10 +13,7 @@ final class PhabricatorEventType extends PhutilEventType {
   const TYPE_MANIPHEST_WILLEDITTASK         = 'maniphest.willEditTask';
   const TYPE_MANIPHEST_DIDEDITTASK          = 'maniphest.didEditTask';
 
-  const TYPE_DIFFERENTIAL_WILLSENDMAIL      = 'differential.willSendMail';
   const TYPE_DIFFERENTIAL_WILLMARKGENERATED = 'differential.willMarkGenerated';
-  const TYPE_DIFFERENTIAL_WILLEDITREVISION  = 'differential.willEditRevision';
-  const TYPE_DIFFERENTIAL_DIDEDITREVISION   = 'differential.didEditRevision';
 
   const TYPE_DIFFUSION_DIDDISCOVERCOMMIT    = 'diffusion.didDiscoverCommit';
   const TYPE_DIFFUSION_LOOKUPUSER           = 'diffusion.lookupUser';