fix(auth): root state validity at active lead

The v3 role-tag work filtered invited and ended listed maintainers, but every announcement author still seeded a repository view. A removed forwarding maintainer or an author with an ended self-role could therefore keep publishing authoritative kind 30618 state through their own coordinate. Parity-only role parsing could also treat malformed histories as active.

Validate numeric role boundaries and the final-end-only defer sentinel, resolve each selected coordinate through one valid active M path to a terminal self-M, and only then seed the reciprocal membership fixpoint. Legacy and explicitly leadless views continue to root at the selected author while that author remains active; incomplete, ambiguous, and cyclic explicit paths fail closed.

This changes current state and maintainer-scoped authorization only. Historical event authorization and membership mutation workflows remain outside the relay-side patch.

Validated with cargo test --lib (902 tests), cargo test --test state_authorization (53 tests), and cargo clippy --tests -- -D warnings.

CHANGELOG.md

@@ -7,6 +7,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- Correct kind `30618` repository-state authority for a view explicitly
+  selected through a former maintainer's coordinate. Previously, only that
+  selected view could continue accepting state signed by the former
+  maintainer after the lead stopped assigning them; this did not restore the
+  former maintainer's authority over views selected through the lead or any
+  other maintainer. Selected views now resolve authority through valid active
+  `M` records to the terminal maintainer. Ended selected authors, malformed
+  role histories, missing or ambiguous lead targets, and lead cycles fail
+  closed.
+
 ## [3.0.0] - 2026-08-20
 
 ### Summary

docs/explanation/architecture.md

@@ -296,16 +296,18 @@ pub struct RepositoryState { ... }
 Announcements carry maintainer listings in two formats:
 
 - **Indexed role tags** (`M` lead, `m` co-maintainer). A tag may record
-  history as alternating start/end timestamps; it is currently active when
-  it has fewer than four elements or an odd number of elements. Ended
-  entries are ignored entirely - the history is only used to conclude a
-  role has *ended*, never to grant authority for a past period. The lead /
-  co-maintainer distinction carries no meaning for this service. A pubkey
-  may appear in multiple role tags: one of each letter records a role
-  transition, and out-of-spec duplicates under the same letter are
-  tolerated. Histories are consolidated - the pubkey is a maintainer while
-  any `M`/`m` entry is active. An author who appears in no role tag is
-  implicitly a maintainer for the repository's entire history.
+  history as alternating numeric start/end timestamps; `defer` is valid only
+  as the final end boundary. It is currently active when it has no boundaries
+  or its final valid boundary is a start. Ended, deferred, and malformed
+  entries grant no authority - the history is only used to conclude a role
+  has *ended*, never to grant authority for a past period. Both `M` and `m`
+  grant maintainer authority, while active `M` records also form the lead
+  path that roots the selected repository view. A pubkey may appear in
+  multiple role tags: one of each letter records a role transition, and
+  out-of-spec duplicates under the same letter are tolerated. Histories are
+  consolidated - the pubkey is a maintainer while any valid `M`/`m` entry is
+  active. An author who appears in no role tag is implicitly a maintainer for
+  the repository's entire history.
 - **Deprecated `maintainers` tag** (fallback). Ignored when `M`/`m` tags
   are present. Without any listing tags the author is the sole maintainer.
   A `u` (subordinate fork) tag has no effect on maintainership.
@@ -331,9 +333,12 @@ Authorization follows a reciprocal membership rule, computed per owner by
   author: an ended `M`/`m` self-entry means the pubkey has left, which
   takes precedence over assignments in other announcements. An author who
   appears in no role tag implicitly asserts maintainership.
-- The owner is always a confirmed maintainer of their own repository:
-  announcing a repository in their namespace is what creates it on this
-  service.
+- A valid active `M` path is followed to a terminal self-`M` before the
+  reciprocal fixpoint is seeded. Without an active `M`, the selected author
+  roots a legacy or deliberately leadless view while their own role is active.
+  Missing, ambiguous, and cyclic explicit paths grant no state authority, and
+  a former maintainer's forwarding coordinate does not restore that signer to
+  the confirmed set.
 
 #### [`policy/state.rs`](src/nostr/policy/state.rs) - State Event Authorization
 

docs/explanation/decisions.md

@@ -215,9 +215,11 @@ NIP-34 maintainers model refined in nips commit `781590b`).
   until its own announcement for the same identifier lists back an existing
   confirmed maintainer.
 - Only confirmed maintainers publish authoritative repository state.
-- The owner is always a confirmed maintainer of their own repository:
-  announcing a repository in their namespace is what creates it on this
-  service.
+- Authority is rooted at the terminal lead reached through valid active `M`
+  records. Without an active `M`, the selected author roots a legacy or
+  deliberately leadless view only while their own role is active. Once an
+  explicit path is followed, a missing target, multiple active targets, or a
+  cycle grants no repository-state authority.
 
 ### Implementation choices
 
@@ -240,15 +242,16 @@ NIP-34 maintainers model refined in nips commit `781590b`).
 - `M` (lead) and `m` (co-maintainer) tags are the primary maintainer
   listing (per the model clarified in nips commit `986edd1`); when present
   the deprecated `maintainers` tag is ignored per NIP-34 (and parsed as
-  empty). The role distinction carries no meaning for this service: both
-  collapse into one maintainer set.
-- Role tags may record history as alternating start/end timestamps; a tag
-  is currently active when it has fewer than four elements or an odd number
-  of elements. Ended entries are ignored entirely: role history is only
-  used to conclude that a pubkey is *no longer* a maintainer, never to
-  grant time-scoped retroactive authority over historic events. The
-  NIP's owner-first precedence for conflicting past-role records is
-  therefore unused.
+  empty). Both grant equal maintainer authority, while active `M` records
+  additionally define the lead path used to root that authority.
+- Role tags may record history as alternating numeric start/end timestamps;
+  `defer` is valid only as the final end boundary. A valid tag is currently
+  active when it has no boundaries or its final boundary is a start. Ended,
+  deferred, and malformed entries grant no authority: role history is only
+  used to conclude that a pubkey is *no longer* a maintainer, never to grant
+  time-scoped retroactive authority over historic events. The NIP's
+  owner-first precedence for conflicting past-role records is therefore
+  unused.
 - A pubkey may appear in multiple role tags: one of each letter records a
   role transition per the NIP, and out-of-spec duplicates under the same
   letter are consolidated rather than rejected - rejecting them would drop
@@ -284,4 +287,3 @@ the `M`/`m` assignments they might carry (the NIP says role combinations
 beyond self-plus-lead SHOULD be avoided unless the author is `M`), and
 moderator membership gets no reciprocal-confirmation treatment. Both only
 matter if status-event authority is ever enforced.
-

src/git/authorization.rs

@@ -316,7 +316,8 @@ pub fn pubkey_authorised_for_repo_owners(
 #[derive(Debug, Default)]
 pub struct RepoMembership {
     /// Pubkeys whose repository state events are authoritative for this
-    /// owner's repository: the owner plus every confirmed maintainer.
+    /// owner's selected repository view: the resolved lead or selected
+    /// leadless/legacy root plus every confirmed maintainer.
     pub state_maintainers: HashSet<String>,
     /// Pubkeys currently listed as maintainers whose own announcement does
     /// not yet list back a confirmed maintainer. Their announcements must
@@ -337,9 +338,12 @@ pub struct RepoMembership {
 /// assignments in other announcements. An author who appears in no role tag
 /// implicitly asserts maintainership for the repository's entire history.
 ///
-/// The owner is always a confirmed maintainer of their own repository:
-/// announcing a repository in their namespace is what creates it on this
-/// service.
+/// An explicit active `M` path is resolved before the fixpoint is seeded. A
+/// self-`M` terminates at the lead; an announcement without an active `M`
+/// seeds its author only when resolution has not already followed an explicit
+/// path. Missing, ambiguous, or cyclic explicit paths grant no authority.
+/// This prevents a removed maintainer's forwarding coordinate from restoring
+/// that signer to the confirmed set.
 pub fn compute_membership(
     announcements: &[RepositoryAnnouncement],
     owner: &str,
@@ -350,11 +354,35 @@ pub fn compute_membership(
             .iter()
             .find(|a| a.event.pubkey.to_hex() == pubkey && a.identifier == identifier)
     };
-    if find(owner).is_none() {
-        return RepoMembership::default();
+    // Resolve the selected coordinate's explicit lead path before seeding
+    // reciprocal membership. With no active M on the selected announcement,
+    // this is a legacy or deliberately leadless view rooted at the selected
+    // author. Once an explicit path is followed, only an active self-M may
+    // terminate it; incomplete, ambiguous, and cyclic paths fail closed.
+    let mut root = owner.to_string();
+    let mut followed_explicit_lead = false;
+    let mut visited = HashSet::new();
+    loop {
+        if !visited.insert(root.clone()) {
+            return RepoMembership::default();
+        }
+        let Some(announcement) = find(&root) else {
+            return RepoMembership::default();
+        };
+        let active_leads = announcement.active_leads();
+        match active_leads.as_slice() {
+            [] if !followed_explicit_lead && announcement.author_role_active() => break,
+            [] => return RepoMembership::default(),
+            [lead] if lead == &root && announcement.author_role_active() => break,
+            [lead] if lead != &root => {
+                root = lead.clone();
+                followed_explicit_lead = true;
+            }
+            _ => return RepoMembership::default(),
+        }
     }
 
-    let mut confirmed: HashSet<String> = HashSet::from([owner.to_string()]);
+    let mut confirmed: HashSet<String> = HashSet::from([root]);
     // Fixpoint: keep confirming listed pubkeys whose own announcement lists
     // back an already-confirmed maintainer. The confirmed set only grows, so
     // the loop terminates.
@@ -1456,6 +1484,131 @@ mod tests {
 
         let membership = compute_membership(&announcements, &hex(&alice), identifier);
         assert!(membership.state_maintainers.contains(&hex(&bob)));
+
+        let selected_from_bob = compute_membership(&announcements, &hex(&bob), identifier);
+        assert_eq!(
+            selected_from_bob.state_maintainers,
+            membership.state_maintainers
+        );
+    }
+
+    #[test]
+    fn test_ended_selected_author_has_no_state_authority() {
+        let alice = create_test_keys();
+        let identifier = "test-repo";
+
+        let announcements = vec![parse(create_role_announcement(
+            &alice,
+            identifier,
+            &[("m", vec![hex(&alice), "100".to_string(), "200".to_string()])],
+        ))];
+
+        let membership = compute_membership(&announcements, &hex(&alice), identifier);
+        assert!(membership.state_maintainers.is_empty());
+        assert!(membership.invited.is_empty());
+    }
+
+    #[test]
+    fn test_removed_selected_maintainer_resolves_lead_without_regaining_authority() {
+        let alice = create_test_keys();
+        let bob = create_test_keys();
+        let identifier = "test-repo";
+
+        // Alice no longer assigns Bob. Bob's still-active acceptance and M
+        // redirect keep the coordinate attached to Alice, but do not seed Bob
+        // as a maintainer of a separate same-identifier repository.
+        let announcements = vec![
+            parse(create_role_announcement(
+                &alice,
+                identifier,
+                &[("M", vec![hex(&alice)])],
+            )),
+            parse(create_role_announcement(
+                &bob,
+                identifier,
+                &[("M", vec![hex(&alice)]), ("m", vec![hex(&bob)])],
+            )),
+        ];
+
+        let membership = compute_membership(&announcements, &hex(&bob), identifier);
+        assert_eq!(membership.state_maintainers, HashSet::from([hex(&alice)]));
+
+        let repo_data = RepositoryData {
+            announcements,
+            states: Vec::new(),
+        };
+        assert!(pubkey_authorised_for_repo_owners(&bob.public_key(), &repo_data).is_empty());
+        assert_eq!(
+            pubkey_authorised_for_repo_owners(&alice.public_key(), &repo_data)
+                .into_iter()
+                .collect::<HashSet<_>>(),
+            HashSet::from([hex(&alice), hex(&bob)])
+        );
+    }
+
+    #[test]
+    fn test_incomplete_ambiguous_or_cyclic_lead_path_grants_no_state_authority() {
+        let alice = create_test_keys();
+        let bob = create_test_keys();
+        let identifier = "test-repo";
+
+        let bob_announcement = parse(create_role_announcement(
+            &bob,
+            identifier,
+            &[("M", vec![hex(&alice)]), ("m", vec![hex(&bob)])],
+        ));
+        let missing_lead = compute_membership(
+            std::slice::from_ref(&bob_announcement),
+            &hex(&bob),
+            identifier,
+        );
+        assert!(missing_lead.state_maintainers.is_empty());
+
+        let ambiguous = parse(create_role_announcement(
+            &alice,
+            identifier,
+            &[("M", vec![hex(&alice)]), ("M", vec![hex(&bob)])],
+        ));
+        let ambiguous_lead = compute_membership(&[ambiguous], &hex(&alice), identifier);
+        assert!(ambiguous_lead.state_maintainers.is_empty());
+
+        let alice_announcement = parse(create_role_announcement(
+            &alice,
+            identifier,
+            &[("M", vec![hex(&bob)]), ("m", vec![hex(&alice)])],
+        ));
+        let cycle = compute_membership(
+            &[alice_announcement, bob_announcement],
+            &hex(&alice),
+            identifier,
+        );
+        assert!(cycle.state_maintainers.is_empty());
+    }
+
+    #[test]
+    fn test_explicit_leadless_roles_still_root_selected_authority() {
+        let alice = create_test_keys();
+        let bob = create_test_keys();
+        let identifier = "test-repo";
+
+        let announcements = vec![
+            parse(create_role_announcement(
+                &alice,
+                identifier,
+                &[("m", vec![hex(&alice)]), ("m", vec![hex(&bob)])],
+            )),
+            parse(create_role_announcement(
+                &bob,
+                identifier,
+                &[("m", vec![hex(&bob)]), ("m", vec![hex(&alice)])],
+            )),
+        ];
+
+        let membership = compute_membership(&announcements, &hex(&alice), identifier);
+        assert_eq!(
+            membership.state_maintainers,
+            HashSet::from([hex(&alice), hex(&bob)])
+        );
     }
 
     #[test]

src/nostr/events.rs

@@ -7,7 +7,32 @@
 /// - NIP-34: https://nips.nostr.com/34
 /// - GRASP-01: https://gitworkshop.dev/danconwaydev.com/grasp/01.md
 use anyhow::{anyhow, Result};
-use nostr_sdk::prelude::{Event, Kind, ToBech32};
+use nostr_sdk::prelude::{Event, Kind, PublicKey, ToBech32};
+
+/// Whether a NIP-34 indexed role record is syntactically valid and active.
+///
+/// Values after the pubkey alternate between numeric start and end
+/// boundaries. `defer` is valid only as the final end boundary and is never
+/// active. Malformed history must not grant repository authority.
+fn role_entry_is_active(slice: &[String]) -> bool {
+    if slice.len() < 2 {
+        return false;
+    }
+
+    let boundaries = &slice[2..];
+    for (index, value) in boundaries.iter().enumerate() {
+        if value == "defer" {
+            let is_final_end = index % 2 == 1 && index + 1 == boundaries.len();
+            if !is_final_end {
+                return false;
+            }
+        } else if value.parse::<u64>().is_err() {
+            return false;
+        }
+    }
+
+    boundaries.is_empty() || boundaries.len() % 2 == 1
+}
 
 // NOTE: Using rust-nostr Kind variants instead of hardcoded constants:
 // - KIND_REPOSITORY_ANNOUNCEMENT -> Kind::GitRepoAnnouncement (30617)
@@ -34,11 +59,11 @@ pub struct RepositoryAnnouncement {
     /// `None` when the announcement contains no role tags. Moderator (`o`)
     /// entries never contribute: moderators are not maintainers.
     ///
-    /// The lead (`M`) / co-maintainer (`m`) distinction carries no meaning
-    /// for this service, so both collapse into one maintainer set. Entries
-    /// whose role history shows the role has ended are excluded entirely: an
-    /// ended role means the pubkey is no longer a maintainer, and historic
-    /// listing never grants authority for a past period.
+    /// Both `M` and `m` grant maintainer authority, so they collapse into one
+    /// maintainer set. Active `M` entries additionally drive lead resolution
+    /// through [`Self::active_leads`]. Entries whose role history is malformed
+    /// or ended are excluded entirely: historic listing never grants
+    /// authority for a past period.
     pub role_maintainers: Option<Vec<String>>,
     /// Whether any role tag names the author, active or ended. Per NIP-34 an
     /// author without a self-entry is implicitly a maintainer for the
@@ -127,13 +152,14 @@ impl RepositoryAnnouncement {
         // Extract maintainer pubkeys from NIP-34 `M`/`m`/`o` role tags
         // Format: ["M"|"m"|"o", "<pubkey-hex>", "<start>", "<end>", ...]
         // A role tag lists a pubkey followed by optional alternating start/end
-        // history timestamps; it is currently active when it has fewer than
-        // four elements or an odd number of elements. Ended entries are
-        // ignored entirely. A pubkey may appear in multiple role tags: one
-        // tag of each letter records transitions between roles, and
-        // out-of-spec duplicates under the same letter are tolerated. The
-        // histories are consolidated - the pubkey is a maintainer while any
-        // of its `M`/`m` entries is active.
+        // history timestamps; it is currently active when it has no history
+        // or its final valid boundary is a start. `defer` is accepted only as
+        // the final end boundary. Ended and malformed entries are ignored for
+        // authority. A pubkey may appear in multiple role tags: one tag of
+        // each letter records transitions between roles, and out-of-spec
+        // duplicates under the same letter are tolerated. The histories are
+        // consolidated - the pubkey is a maintainer while any of its valid
+        // `M`/`m` entries is active.
         //
         // The moderator role (`o`) grants no maintainership: moderators are
         // only empowered to have status events (kinds 1630-1633) treated as
@@ -144,7 +170,6 @@ impl RepositoryAnnouncement {
         // counts as a role tag: its presence suppresses the deprecated
         // `maintainers` fallback, and a self-`o` entry is a self-role, so
         // the author is not implicitly a maintainer.
-        let author_hex = event.pubkey.to_hex();
         let mut role_tags_present = false;
         let mut author_has_role_entry = false;
         let mut role_active: Vec<String> = Vec::new();
@@ -158,15 +183,21 @@ impl RepositoryAnnouncement {
             let Some(pubkey) = slice.get(1).filter(|value| !value.is_empty()) else {
                 continue;
             };
-            if *pubkey == author_hex {
+            let parsed_pubkey = PublicKey::from_hex(pubkey).ok();
+            if parsed_pubkey.as_ref() == Some(&event.pubkey) {
                 author_has_role_entry = true;
             }
             if kind == "o" {
                 continue;
             }
-            let active = slice.len() < 4 || slice.len() % 2 == 1;
-            if active && !role_active.contains(pubkey) {
-                role_active.push(pubkey.clone());
+            if role_entry_is_active(slice) {
+                let Some(parsed_pubkey) = parsed_pubkey else {
+                    continue;
+                };
+                let pubkey = parsed_pubkey.to_hex();
+                if !role_active.contains(&pubkey) {
+                    role_active.push(pubkey);
+                }
             }
         }
         let role_maintainers = role_tags_present.then_some(role_active);
@@ -226,6 +257,32 @@ impl RepositoryAnnouncement {
         listed
     }
 
+    /// Distinct targets of syntactically valid, currently-active `M` records.
+    ///
+    /// An active `M` is both a maintainer edge and an explicit lead pointer.
+    /// Duplicate records for one target are consolidated; distinct targets
+    /// remain visible so authority resolution can fail closed on ambiguity.
+    pub fn active_leads(&self) -> Vec<String> {
+        let mut leads = Vec::new();
+        for tag in self.event.tags.iter() {
+            let slice = tag.as_slice();
+            if slice.first().map(String::as_str) != Some("M") || !role_entry_is_active(slice) {
+                continue;
+            }
+            let Some(pubkey) = slice
+                .get(1)
+                .and_then(|value| PublicKey::from_hex(value).ok())
+            else {
+                continue;
+            };
+            let pubkey = pubkey.to_hex();
+            if !leads.contains(&pubkey) {
+                leads.push(pubkey);
+            }
+        }
+        leads
+    }
+
     /// Whether this announcement asserts an active maintainer role for its
     /// own author.
     ///
@@ -928,20 +985,22 @@ mod tests {
     }
 
     #[test]
-    fn test_role_tag_activeness_by_element_count() {
+    fn test_role_tag_activeness_requires_valid_history() {
         let keys = create_test_keys();
         let author = keys.public_key().to_hex();
         let other = create_test_keys().public_key().to_hex();
 
         // (history values after the pubkey, expected active)
-        // Tag element counts: 2 -> active, 3 -> active, 4 -> ended,
-        // 5 -> active, 6 -> ended.
         let cases: Vec<(Vec<&str>, bool)> = vec![
             (vec![], true),
             (vec!["100"], true),
             (vec!["100", "200"], false),
             (vec!["100", "200", "300"], true),
             (vec!["100", "200", "300", "400"], false),
+            (vec!["100", "defer"], false),
+            (vec!["not-a-timestamp"], false),
+            (vec!["defer"], false),
+            (vec!["100", "defer", "300"], false),
         ];
 
         for (history, expected_active) in cases {
@@ -957,6 +1016,28 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_active_leads_include_only_valid_distinct_targets() {
+        let keys = create_test_keys();
+        let first = create_test_keys().public_key().to_hex();
+        let second = create_test_keys().public_key().to_hex();
+        let ended = create_test_keys().public_key().to_hex();
+        let malformed = create_test_keys().public_key().to_hex();
+
+        let announcement = role_announcement(
+            &keys,
+            vec![
+                ("M", vec![first.clone()]),
+                ("M", vec![first.clone(), "100".to_string()]),
+                ("M", vec![second.clone()]),
+                ("M", vec![ended, "100".to_string(), "200".to_string()]),
+                ("M", vec![malformed, "not-a-timestamp".to_string()]),
+            ],
+        );
+
+        assert_eq!(announcement.active_leads(), vec![first, second]);
+    }
+
     #[test]
     fn test_lead_and_co_maintainer_roles_are_equivalent() {
         let keys = create_test_keys();

tests/state_authorization.rs

@@ -297,6 +297,81 @@ async fn state_event_rejected_as_unauthorized(client: &Client, keys: &Keys) -> b
     }
 }
 
+#[tokio::test]
+async fn test_reject_state_from_announcement_author_with_ended_self_role() {
+    let relay = TestRelay::start().await;
+    let owner_keys = Keys::generate();
+
+    let announcement = EventBuilder::new(Kind::GitRepoAnnouncement, "")
+        .tags([
+            Tag::custom("d", ["test-repo"]),
+            Tag::custom("clone", [format!("https://{}/test.git", relay.domain())]),
+            Tag::custom("relays", [relay.url()]),
+            Tag::custom(
+                "m",
+                [
+                    owner_keys.public_key().to_hex(),
+                    "0".to_string(),
+                    "1700000000".to_string(),
+                ],
+            ),
+        ])
+        .finalize(&owner_keys)
+        .unwrap();
+
+    let client = Client::default();
+    client.add_relay(relay.url()).await.unwrap();
+    client.connect().await;
+    client.send_event(&announcement).await.unwrap();
+
+    assert!(
+        state_event_rejected_as_unauthorized(&client, &owner_keys).await,
+        "an ended selected author's state event must be rejected as unauthorized"
+    );
+
+    relay.stop().await;
+}
+
+#[tokio::test]
+async fn test_reject_state_from_unassigned_forwarding_author() {
+    let relay = TestRelay::start().await;
+    let lead_keys = Keys::generate();
+    let former_keys = Keys::generate();
+
+    let lead_announcement = EventBuilder::new(Kind::GitRepoAnnouncement, "")
+        .tags([
+            Tag::custom("d", ["test-repo"]),
+            Tag::custom("clone", [format!("https://{}/test.git", relay.domain())]),
+            Tag::custom("relays", [relay.url()]),
+            Tag::custom("M", [lead_keys.public_key().to_hex()]),
+        ])
+        .finalize(&lead_keys)
+        .unwrap();
+    let former_announcement = EventBuilder::new(Kind::GitRepoAnnouncement, "")
+        .tags([
+            Tag::custom("d", ["test-repo"]),
+            Tag::custom("clone", [format!("https://{}/test.git", relay.domain())]),
+            Tag::custom("relays", [relay.url()]),
+            Tag::custom("M", [lead_keys.public_key().to_hex()]),
+            Tag::custom("m", [former_keys.public_key().to_hex()]),
+        ])
+        .finalize(&former_keys)
+        .unwrap();
+
+    let client = Client::default();
+    client.add_relay(relay.url()).await.unwrap();
+    client.connect().await;
+    client.send_event(&lead_announcement).await.unwrap();
+    client.send_event(&former_announcement).await.unwrap();
+
+    assert!(
+        state_event_rejected_as_unauthorized(&client, &former_keys).await,
+        "a forwarding signer not assigned by the lead must not regain state authority"
+    );
+
+    relay.stop().await;
+}
+
 #[tokio::test]
 async fn test_reject_state_from_invited_maintainer() {
     let relay = TestRelay::start().await;