diff --git a/services/blob/src/constants.rs b/services/blob/src/constants.rs
--- a/services/blob/src/constants.rs
+++ b/services/blob/src/constants.rs
@@ -23,6 +23,7 @@
   /// attribute names
   pub const ATTR_BLOB_HASH: &str = "blob_hash";
   pub const ATTR_HOLDER: &str = "holder";
+  pub const ATTR_INDEXED_TAG: &str = "indexed_tag";
   pub const ATTR_CREATED_AT: &str = "created_at";
   pub const ATTR_LAST_MODIFIED: &str = "last_modified";
   pub const ATTR_S3_PATH: &str = "s3_path";
diff --git a/services/blob/src/database/client.rs b/services/blob/src/database/client.rs
--- a/services/blob/src/database/client.rs
+++ b/services/blob/src/database/client.rs
@@ -99,13 +99,19 @@
     let blob_hash: String = blob_hash.into();
     let holder: String = holder.into();
 
+    let indexed_tag = get_indexable_tag(&holder, &[]);
+
     validate_holder(&holder)?;
-    let item = HashMap::from([
+    let mut item = HashMap::from([
       (ATTR_BLOB_HASH.to_string(), AttributeValue::S(blob_hash)),
       (ATTR_HOLDER.to_string(), AttributeValue::S(holder)),
       (ATTR_UNCHECKED.to_string(), UncheckedKind::Holder.into()),
     ]);
 
+    if let Some(tag) = indexed_tag {
+      item.insert(ATTR_INDEXED_TAG.to_string(), AttributeValue::S(tag));
+    }
+
     self.insert_item(item).await?;
     Ok(())
   }
@@ -434,3 +440,59 @@
   }
   Ok(())
 }
+
+/// In the future we'll want to add a `tags` meta attribute for internal
+/// use, e.g. in case of data loss on other services. The attribute
+/// is going to be a list of string values - _tags_.
+/// First tag from the list is going to be indexed in DDB.
+///
+/// While tags are not implemented, we accept _holder prefixes_
+/// as an intermediate solution - holder prefix (separated by the `:` character)
+/// is treated as the first holder _tag_, unless [`tags`] is not empty.
+fn get_indexable_tag(holder: &str, tags: &[String]) -> Option<String> {
+  const HOLDER_PREFIX_SEPARATOR: char = ':';
+
+  if let Some(first_tag) = tags.first() {
+    return Some(first_tag.to_string());
+  }
+
+  if !holder.contains(HOLDER_PREFIX_SEPARATOR) {
+    return None;
+  }
+
+  holder
+    .split(HOLDER_PREFIX_SEPARATOR)
+    .next()
+    .map(str::to_string)
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn get_indexable_tag_no_tags_no_prefix() {
+    let tag = get_indexable_tag("foo", &[]);
+    assert!(tag.is_none());
+  }
+
+  #[test]
+  fn get_indexable_tag_tags_no_prefix() {
+    let tags = vec!["tag1".to_string(), "tag2".to_string()];
+    let tag = get_indexable_tag("foo", &tags);
+    assert_eq!(tag, Some("tag1".into()));
+  }
+
+  #[test]
+  fn get_indexable_tag_tags_and_prefix() {
+    let tags = vec!["tag1".to_string(), "tag2".to_string()];
+    let tag = get_indexable_tag("device1:foo", &tags);
+    assert_eq!(tag, Some("tag1".into()));
+  }
+
+  #[test]
+  fn get_indexable_tag_prefix_no_tags() {
+    let tag = get_indexable_tag("device1:foo", &[]);
+    assert_eq!(tag, Some("device1".into()));
+  }
+}