diff --git a/zipline/protocol.py b/zipline/protocol.py
index 8ff24389..7081291f 100644
--- a/zipline/protocol.py
+++ b/zipline/protocol.py
@@ -495,7 +495,6 @@ def convert_transactions(transactions):
     for txn in transactions:
         txn['date'] = EPOCH(txn['dt'])
         del(txn['dt'])
-        del(txn['source_id'])
         results.append(txn)
     return results