diff --git a/crates/tiny-artifacts/tests/publish_file_changed.rs b/crates/tiny-artifacts/tests/publish_file_changed.rs
new file mode 100644
index 0000000..40f5e49
--- /dev/null
+++ b/crates/tiny-artifacts/tests/publish_file_changed.rs
@@ -0,0 +1,139 @@
+//! Sharing an older file version: allowed while the stored file is still the
+//! one that version recorded, refused once it has changed or cannot be checked.
+
+#![allow(clippy::unwrap_used, clippy::expect_used)]
+
+use std::path::PathBuf;
+use std::sync::{Arc, Mutex};
+
+use tiny_artifacts::{
+    ArtifactKind, ArtifactPublisher, ArtifactRecord, ArtifactStore, ArtifactVersion, Artifacts,
+    ArtifactsError, Author, BlobFileStore, Content, FileRoots, FileStore, PublishOptions,
+    PublishedLink,
+};
+use tinystoragedrivers_testkit::memory_storage;
+use tinystoragedrivers_types::Scope;
+
+#[derive(Default)]
+struct MemStore(Mutex<Vec<ArtifactRecord>>);
+
+#[async_trait::async_trait]
+impl ArtifactStore for MemStore {
+    async fn list(&self) -> anyhow::Result<Vec<ArtifactRecord>> {
+        Ok(self.0.lock().unwrap().clone())
+    }
+    async fn get(&self, id: &str) -> anyhow::Result<Option<ArtifactRecord>> {
+        Ok(self.0.lock().unwrap().iter().find(|r| r.id == id).cloned())
+    }
+    async fn upsert(&self, artifact: &ArtifactRecord) -> anyhow::Result<()> {
+        let mut store = self.0.lock().unwrap();
+        store.retain(|r| r.id != artifact.id);
+        store.push(artifact.clone());
+        Ok(())
+    }
+    async fn delete(&self, id: &str) -> anyhow::Result<bool> {
+        let mut store = self.0.lock().unwrap();
+        let before = store.len();
+        store.retain(|r| r.id != id);
+        Ok(store.len() < before)
+    }
+}
+
+struct LinkPublisher;
+
+#[async_trait::async_trait]
+impl ArtifactPublisher for LinkPublisher {
+    async fn publish(
+        &self,
+        record: &ArtifactRecord,
+        version: &ArtifactVersion,
+        options: &PublishOptions,
+    ) -> anyhow::Result<PublishedLink> {
+        Ok(PublishedLink {
+            url: format!("https://share.example/{}/v{}", record.id, version.version),
+            expires_at_millis: Some(u64::MAX),
+            published_at_millis: 1,
+            public: options.public,
+        })
+    }
+}
+
+fn workdir() -> PathBuf {
+    let dir = std::env::temp_dir().join(format!("tiny-artifacts-{}", uuid::Uuid::new_v4()));
+    std::fs::create_dir_all(&dir).unwrap();
+    dir
+}
+
+#[tokio::test]
+async fn an_older_file_version_is_refused_once_its_stored_file_changed() {
+    let root = workdir();
+    std::fs::write(root.join("deck.pptx"), b"v1").unwrap();
+    let store = Arc::new(MemStore::default());
+    let files = Arc::new(BlobFileStore::new(&memory_storage(
+        &Scope::new("artifact-publish-test").unwrap(),
+    )));
+    let artifacts = Artifacts::new(store.clone())
+        .with_publisher(Arc::new(LinkPublisher))
+        .with_file_roots(FileRoots::new([root.clone()]))
+        .with_file_store(files.clone());
+    let author = Author::agent("a");
+    let id = artifacts
+        .create(
+            ArtifactKind::File,
+            "Deck",
+            Content::File("deck.pptx".into()),
+            &author,
+            None,
+        )
+        .await
+        .unwrap()
+        .record
+        .id;
+    std::fs::write(root.join("deck.pptx"), b"v2-longer").unwrap();
+    artifacts
+        .revise(&id, Content::File("deck.pptx".into()), &author, None)
+        .await
+        .unwrap();
+    let fresh = PublishOptions {
+        fresh: true,
+        ..PublishOptions::default()
+    };
+
+    // The stored v1 file is still the one v1 recorded.
+    assert_eq!(
+        artifacts
+            .publish(&id, Some(1), &fresh)
+            .await
+            .unwrap()
+            .version,
+        1
+    );
+
+    // A host without a file store cannot check it, so it refuses.
+    let unchecked = Artifacts::new(store.clone()).with_publisher(Arc::new(LinkPublisher));
+    assert!(matches!(
+        unchecked.publish(&id, Some(1), &fresh).await,
+        Err(ArtifactsError::FileChanged { version: 1, .. })
+    ));
+
+    // Once the stored v1 file is replaced with different bytes, v1 is refused.
+    let record = artifacts.get(&id).await.unwrap().unwrap();
+    let key = record
+        .version(1)
+        .unwrap()
+        .file
+        .as_ref()
+        .unwrap()
+        .key
+        .clone();
+    files.put(&key, b"replaced, longer", None).await.unwrap();
+    assert!(matches!(
+        artifacts.publish(&id, Some(1), &fresh).await,
+        Err(ArtifactsError::FileChanged { version: 1, .. })
+    ));
+    // The newest version is unaffected.
+    assert_eq!(
+        artifacts.publish(&id, None, &fresh).await.unwrap().version,
+        2
+    );
+}