diff --git a/rust_snuba/src/processors/outcomes.rs b/rust_snuba/src/processors/outcomes.rs
index 7d81b9a8ea..e885f64f44 100644
--- a/rust_snuba/src/processors/outcomes.rs
+++ b/rust_snuba/src/processors/outcomes.rs
@@ -33,6 +33,8 @@ const CLIENT_DISCARD_REASONS: &[&str] = &[
     "invalid",
     // events were dropped because of network errors and were not retried.
     "network_error",
+    // a span was dropped or not started by an SDK due to a missing parent span
+    "no_parent_span",
     // a SDK internal queue (eg: transport queue) overflowed
     "queue_overflow",
     // the SDK dropped events because an earlier rate limit instructed the SDK to back off.