diff --git a/docs/streams/developer-guide/dsl-api.html b/docs/streams/developer-guide/dsl-api.html
index e54d4491c739a..02f2441a57db7 100644
--- a/docs/streams/developer-guide/dsl-api.html
+++ b/docs/streams/developer-guide/dsl-api.html
@@ -261,7 +261,7 @@ <h4><a id="streams_concepts_globalktable" href="#streams_concepts_globalktable">
                         <p>You <strong>must specify SerDes explicitly</strong> if the key or value types of the records in the Kafka input
                             topics do not match the configured default SerDes. For information about configuring default SerDes, available
                             SerDes, and implementing your own custom SerDes see <a class="reference internal" href="datatypes.html#streams-developer-guide-serdes"><span class="std std-ref">Data Types and Serialization</span></a>.</p>
-                        <p class="last">Several variants of <code class="docutils literal"><span class="pre">stream</span></code> exist, for example to specify a regex pattern for input topics to read from).</p>
+                        <p class="last">Several variants of <code class="docutils literal"><span class="pre">stream</span></code> exist. For example, you can specify a regex pattern for input topics to read from (note that all matching topics will be part of the same input topic group, and the work will not be parallelized for different topics if subscribed to in this way).</p>
                     </td>
                 </tr>
                 <tr class="row-odd"><td><p class="first"><strong>Table</strong></p>
diff --git a/streams/src/main/java/org/apache/kafka/streams/StreamsBuilder.java b/streams/src/main/java/org/apache/kafka/streams/StreamsBuilder.java
index 609bce5caabaa..8d650d2dcefa5 100644
--- a/streams/src/main/java/org/apache/kafka/streams/StreamsBuilder.java
+++ b/streams/src/main/java/org/apache/kafka/streams/StreamsBuilder.java
@@ -148,7 +148,9 @@ public synchronized <K, V> KStream<K, V> stream(final Collection<String> topics,
      * deserializers as specified in the {@link StreamsConfig config} are used.
      * <p>
      * If multiple topics are matched by the specified pattern, the created {@link KStream} will read data from all of
-     * them and there is no ordering guarantee between records from different topics.
+     * them and there is no ordering guarantee between records from different topics. This also means that the work
+     * will not be parallelized for multiple topics, and the number of tasks will scale with the maximum partition
+     * count of any matching topic rather than the total number of partitions across all topics.
      * <p>
      * Note that the specified input topics must be partitioned by key.
      * If this is not the case it is the user's responsibility to repartition the data before any key based operation
@@ -167,7 +169,9 @@ public synchronized <K, V> KStream<K, V> stream(final Pattern topicPattern) {
      * are defined by the options in {@link Consumed} are used.
      * <p>
      * If multiple topics are matched by the specified pattern, the created {@link KStream} will read data from all of
-     * them and there is no ordering guarantee between records from different topics.
+     * them and there is no ordering guarantee between records from different topics. This also means that the work
+     * will not be parallelized for multiple topics, and the number of tasks will scale with the maximum partition
+     * count of any matching topic rather than the total number of partitions across all topics.
      * <p>
      * Note that the specified input topics must be partitioned by key.
      * If this is not the case it is the user's responsibility to repartition the data before any key based operation