diff --git a/draft-ietf-quic-transport.md b/draft-ietf-quic-transport.md
index ada8036f37..566be4055a 100644
--- a/draft-ietf-quic-transport.md
+++ b/draft-ietf-quic-transport.md
@@ -3612,10 +3612,18 @@ When new data is to be sent on a stream, a sender MUST set the encapsulating
 STREAM frame's offset field to the stream offset of the first byte of this new
 data.  The first octet of data on a stream has an offset of 0.  An endpoint is
 expected to send every stream octet.  The largest offset delivered on a stream
-MUST be less than 2^62. A receiver MUST ensure that received stream data is
-delivered to the application as an ordered byte-stream.  Data received out of
-order MUST be buffered for later delivery, as long as it is not in violation of
-the receiver's flow control limits.
+MUST be less than 2^62.
+
+QUIC makes no specific allowances for partial reliability or delivery of stream
+data out of order.  Endpoints MUST be able to deliver stream data to an
+application as an ordered byte-stream.  Delivering an ordered byte-stream
+requires that an endpoint buffer any data that is received out of order, up to
+the advertised flow control limit.
+
+An endpoint could receive the same octets multiple times; octets that have
+already been received can be discarded.  The value for a given octet MUST NOT
+change if it is sent multiple times; an endpoint MAY treat receipt of a changed
+octet as a connection error of type PROTOCOL_VIOLATION.
 
 An endpoint MUST NOT send data on any stream without ensuring that it is within
 the data limits set by its peer.  The cryptographic handshake stream, Stream 0,