diff --git a/include/haproxy/quic_conn.h b/include/haproxy/quic_conn.h
index b52535ff3..a3cd423d2 100644
--- a/include/haproxy/quic_conn.h
+++ b/include/haproxy/quic_conn.h
@@ -208,17 +208,6 @@ static inline void quic_connection_id_to_frm_cpy(struct quic_frame *dst,
 	to->stateless_reset_token = src->stateless_reset_token;
 }
 
-/* Modify <cid> to have a CID linked to the thread ID <target_tid> that
- * quic_get_cid_tid() will be able to extract return.
- */
-static inline void quic_pin_cid_to_tid(unsigned char *cid, uint target_tid)
-{
-	uint16_t prev_id;
-
-	prev_id = read_n16(cid);
-	write_n16(cid, (prev_id & ~4095) | target_tid);
-}
-
 /* Return a 32-bits integer in <val> from QUIC packet with <buf> as address.
  * Makes <buf> point to the data after this 32-bits value if succeeded.
  * Note that these 32-bits integers are network bytes ordered.
diff --git a/src/quic_conn.c b/src/quic_conn.c
index 1a6d1176a..e4145f6dc 100644
--- a/src/quic_conn.c
+++ b/src/quic_conn.c
@@ -3906,8 +3906,7 @@ static int quic_stateless_reset_token_init(struct quic_connection_id *conn_id)
 	return ret;
 }
 
-/* Generate a CID directly derived from <orig> CID and <addr> address. The CID
- * is then marked with the current thread ID.
+/* Generate a CID directly derived from <orig> CID and <addr> address.
  *
  * Returns the derived CID.
  */
@@ -3962,9 +3961,6 @@ struct quic_cid quic_derive_cid(const struct quic_cid *orig,
 		cid.data[i] = hash >> ((sizeof(hash) * 7) - (8 * i));
 	cid.len = sizeof(hash);
 
-	/* Mark the current thread id in the CID. */
-	quic_pin_cid_to_tid(cid.data, tid);
-
 	return cid;
 }
 
@@ -4055,7 +4051,6 @@ static struct quic_connection_id *new_quic_cid(struct eb_root *root,
 			TRACE_ERROR("RAND_bytes() failed", QUIC_EV_CONN_TXPKT, qc);
 			goto err;
 		}
-		quic_pin_cid_to_tid(conn_id->cid.data, tid);
 	}
 	else {
 		/* Derive the new CID value from original CID. */