diff --git a/app/assets/javascripts/components/features/compose/components/compose_form.jsx b/app/assets/javascripts/components/features/compose/components/compose_form.jsx
index 166c5fdced..9edc01ed76 100644
--- a/app/assets/javascripts/components/features/compose/components/compose_form.jsx
+++ b/app/assets/javascripts/components/features/compose/components/compose_form.jsx
@@ -36,6 +36,8 @@ const ComposeForm = React.createClass({
     in_reply_to: ImmutablePropTypes.map,
     media_count: React.PropTypes.number,
     me: React.PropTypes.number,
+    needsPrivacyWarning: React.PropTypes.bool,
+    mentionedDomains: React.PropTypes.array.isRequired,
     onChange: React.PropTypes.func.isRequired,
     onSubmit: React.PropTypes.func.isRequired,
     onCancelReply: React.PropTypes.func.isRequired,
@@ -117,16 +119,29 @@ const ComposeForm = React.createClass({
   },
 
   render () {
-    const { intl }  = this.props;
-    let replyArea   = '';
-    let publishText = '';
-    const disabled  = this.props.is_submitting || this.props.is_uploading;
+    const { intl, needsPrivacyWarning, mentionedDomains } = this.props;
+    const disabled = this.props.is_submitting || this.props.is_uploading;
+
+    let replyArea      = '';
+    let publishText    = '';
+    let privacyWarning = '';
+    let reply_to_other = !!this.props.in_reply_to && (this.props.in_reply_to.getIn(['account', 'id']) !== this.props.me);
 
     if (this.props.in_reply_to) {
       replyArea = <ReplyIndicator status={this.props.in_reply_to} onCancel={this.props.onCancelReply} />;
     }
 
-    let reply_to_other = !!this.props.in_reply_to && (this.props.in_reply_to.getIn(['account', 'id']) !== this.props.me);
+    if (needsPrivacyWarning) {
+      privacyWarning = (
+        <div className='compose-form__warning'>
+          <FormattedMessage
+            id='compose_form.privacy_disclaimer'
+            defaultMessage='Your private status will be delivered to mentioned users on {domains}. Do you trust {domainsCount, plural, one {that server} other {those servers}} to not leak your status?'
+            values={{ domains: <strong>{mentionedDomains.join(', ')}</strong>, domainsCount: mentionedDomains.length }}
+          />
+        </div>
+      );
+    }
 
     if (this.props.private) {
       publishText = <span><i className='fa fa-lock' /> {intl.formatMessage(messages.publish)}</span>;
@@ -142,6 +157,7 @@ const ComposeForm = React.createClass({
           </div>
         </Collapsable>
 
+        {privacyWarning}
         {replyArea}
 
         <AutosuggestTextarea
@@ -173,13 +189,6 @@ const ComposeForm = React.createClass({
           <Toggle checked={this.props.private} onChange={this.handleChangeVisibility} />
           <span className='compose-form__label__text'><FormattedMessage id='compose_form.private' defaultMessage='Mark as private' /></span>
         </label>
-       
-        <Motion defaultStyle={{ opacity: 0, height: 0 }}, style={{ opacity: spring((this.props.private || reply_to_other) ? 0 : 100), height: spring((this.props.private || reply_to_other) ? 0 : 39.5) }}>
-            <label className='compose-form__label' style={{ height: `${height}px`, overflow: 'hidden', opacity: opacity / 100 }}>
-              <span className='compose-form__label__text'><FormattedMessage id='compose_form.privacy_disclaimer' defaultMessage='Warning: Private posts are not encrypted, and could be read or boosted by instances or people who do not respect post privacy. This is not true privacy. Do not post senstive information.' /></span>
-            </label>
-          }
-        </Motion>
 
         <Collapsable isVisible={!(this.props.private || reply_to_other)} fullHeight={39.5}>
           <label className='compose-form__label'>
diff --git a/app/assets/javascripts/components/features/compose/containers/compose_form_container.jsx b/app/assets/javascripts/components/features/compose/containers/compose_form_container.jsx
index c027875cdc..2671ea618b 100644
--- a/app/assets/javascripts/components/features/compose/containers/compose_form_container.jsx
+++ b/app/assets/javascripts/components/features/compose/containers/compose_form_container.jsx
@@ -19,6 +19,8 @@ const makeMapStateToProps = () => {
   const getStatus = makeGetStatus();
 
   const mapStateToProps = function (state, props) {
+    const mentionedUsernamesWithDomains = state.getIn(['compose', 'text']).match(/(?:^|[^\/\w])@([a-z0-9_]+@[a-z0-9\.\-]+)/ig);
+
     return {
       text: state.getIn(['compose', 'text']),
       suggestion_token: state.getIn(['compose', 'suggestion_token']),
@@ -34,6 +36,8 @@ const makeMapStateToProps = () => {
       in_reply_to: getStatus(state, state.getIn(['compose', 'in_reply_to'])),
       media_count: state.getIn(['compose', 'media_attachments']).size,
       me: state.getIn(['compose', 'me']),
+      needsPrivacyWarning: state.getIn(['compose', 'private']) && mentionedUsernamesWithDomains !== null,
+      mentionedDomains: mentionedUsernamesWithDomains !== null ? [...new Set(mentionedUsernamesWithDomains.map(item => item.split('@')[2]))] : []
     };
   };
 
diff --git a/app/assets/javascripts/components/locales/en.jsx b/app/assets/javascripts/components/locales/en.jsx
index d1357227e5..95962fd738 100644
--- a/app/assets/javascripts/components/locales/en.jsx
+++ b/app/assets/javascripts/components/locales/en.jsx
@@ -41,7 +41,7 @@ const en = {
   "compose_form.sensitive": "Mark media as sensitive",
   "compose_form.spoiler": "Hide text behind warning",
   "compose_form.private": "Mark as private",
-  "compose_form.privacy_disclaimer": "Warning: Private posts are not encrypted, and could be read or boosted by instances or people who do not respect post privacy. This is not true privacy. Do not post senstive information."
+  "compose_form.privacy_disclaimer": "Your private status will be delivered to mentioned users on {domains}. Do you trust {domainsCount, plural, one {that server} other {those servers}} to not leak your status?",
   "compose_form.unlisted": "Do not display in public timeline",
   "navigation_bar.edit_profile": "Edit profile",
   "navigation_bar.preferences": "Preferences",
diff --git a/app/assets/stylesheets/components.scss b/app/assets/stylesheets/components.scss
index f0948b0f39..247ea3132e 100644
--- a/app/assets/stylesheets/components.scss
+++ b/app/assets/stylesheets/components.scss
@@ -78,6 +78,21 @@
   color: $color1;
 }
 
+.compose-form__warning {
+  color: $color2;
+  margin-bottom: 15px;
+  border: 1px solid $color3;
+  padding: 8px 10px;
+  border-radius: 4px;
+  font-size: 12px;
+  font-weight: 400;
+
+  strong {
+    color: $color5;
+    font-weight: 500;
+  }
+}
+
 .compose-form__label {
   display: block;
   line-height: 24px;