diff --git a/services/blob/src/http/handlers/holders.rs b/services/blob/src/http/handlers/holders.rs
--- a/services/blob/src/http/handlers/holders.rs
+++ b/services/blob/src/http/handlers/holders.rs
@@ -1,5 +1,6 @@
-use actix_web::error::ErrorBadRequest;
+use actix_web::error::{ErrorBadRequest, ErrorForbidden};
 use actix_web::{web, HttpResponse};
+use comm_lib::auth::AuthorizationCredential;
 use serde::{Deserialize, Serialize};
 use tracing::{info, instrument, trace, warn};
 
@@ -128,6 +129,36 @@
   Ok(HttpResponse::Ok().json(web::Json(response)))
 }
 
+#[derive(Deserialize)]
+pub struct HoldersQueryUrlParams {
+  prefix: String,
+}
+
+#[derive(Serialize)]
+pub struct HoldersQueryResponse {
+  items: Vec<BlobHashAndHolder>,
+}
+
+#[instrument(name = "query_holders", skip_all)]
+pub async fn query_holders_handler(
+  service: web::Data<BlobService>,
+  query: web::Query<HoldersQueryUrlParams>,
+  requesting_identity: AuthorizationCredential,
+) -> actix_web::Result<HttpResponse> {
+  match requesting_identity {
+    AuthorizationCredential::ServicesToken(_) => (),
+    _ => {
+      return Err(ErrorForbidden(
+        "This endpoint can only be called by other services",
+      ));
+    }
+  };
+  let HoldersQueryUrlParams { prefix } = query.into_inner();
+  let items = service.query_indexed_holders(prefix).await?;
+  let response = HoldersQueryResponse { items };
+  Ok(HttpResponse::Ok().json(web::Json(response)))
+}
+
 /**
  * Returns `HTTP 400 Bad Request` if one or more blob hashes or holders
  * have invalid format. See [`comm_lib::tools::is_valid_identifier`] for
diff --git a/services/blob/src/http/mod.rs b/services/blob/src/http/mod.rs
--- a/services/blob/src/http/mod.rs
+++ b/services/blob/src/http/mod.rs
@@ -48,6 +48,7 @@
       .service(
         web::resource("/holders")
           .wrap(auth_middleware)
+          .route(web::get().to(handlers::holders::query_holders_handler))
           .route(web::post().to(handlers::holders::assign_holders_handler))
           .route(web::delete().to(handlers::holders::remove_holders_handler)),
       )