diff --git a/pkg/coredata/document_version.go b/pkg/coredata/document_version.go
index f2fff6992..254cde23a 100644
--- a/pkg/coredata/document_version.go
+++ b/pkg/coredata/document_version.go
@@ -253,7 +253,7 @@ VALUES (
 		var pgErr *pgconn.PgError
 		if errors.As(err, &pgErr) {
 			if pgErr.Code == "23505" {
-				if pgErr.ConstraintName == "document_versions_document_id_major_minor_key" || pgErr.ConstraintName == "document_one_draft_version_idx" {
+				if pgErr.ConstraintName == "document_versions_document_id_major_minor_key" || pgErr.ConstraintName == "document_one_active_version_idx" {
 					return ErrResourceAlreadyExists
 				}
 			}
diff --git a/pkg/coredata/migrations/20260414T120000Z.sql b/pkg/coredata/migrations/20260414T120000Z.sql
new file mode 100644
index 000000000..90e55b3b0
--- /dev/null
+++ b/pkg/coredata/migrations/20260414T120000Z.sql
@@ -0,0 +1,38 @@
+-- Copyright (c) 2026 Probo Inc <hello@probo.inc>
+--
+-- Permission to use, copy, modify, and distribute this software for any
+-- purpose with or without fee is hereby granted, provided that the above
+-- copyright notice and this permission notice appear in all copies.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+-- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+-- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+-- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+-- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+-- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+-- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+-- The index constraint is already respected in Probo's production environment.
+-- The deletion is here in case duplicates were created directly via SQL in
+-- other contexts.
+DELETE FROM document_versions
+WHERE status IN ('DRAFT', 'PENDING_APPROVAL')
+  AND document_id IN (
+    SELECT document_id
+    FROM document_versions
+    WHERE status IN ('DRAFT', 'PENDING_APPROVAL')
+    GROUP BY document_id
+    HAVING COUNT(*) > 1
+  )
+  AND id NOT IN (
+    SELECT DISTINCT ON (document_id) id
+    FROM document_versions
+    WHERE status IN ('DRAFT', 'PENDING_APPROVAL')
+    ORDER BY document_id, CASE WHEN status = 'PENDING_APPROVAL' THEN 0 ELSE 1 END, created_at ASC
+  );
+
+DROP INDEX document_one_draft_version_idx;
+
+CREATE UNIQUE INDEX document_one_active_version_idx
+    ON document_versions (document_id)
+    WHERE status IN ('DRAFT', 'PENDING_APPROVAL');