diff --git a/ynewsletters/06152023.md b/ynewsletters/06152023.md
new file mode 100644
index 0000000..1359693
--- /dev/null
+++ b/ynewsletters/06152023.md
@@ -0,0 +1,17 @@
+# Malware Behavior Catalog Newsletter #
+**June 15, 2023**
+
+Hello everyone!
+
+Highlights of recent MBC developments include:
+
+* Refined the [STIX 2.1 Malware Behavior Extension](https://docs.google.com/document/d/1azr8ewNXhWyLt1a2wE2cG964QuFSPdIBSqCJFJrwEVo/edit?usp=sharing), which includes new STIX domain objects for MBC objectives, behaviors, and methods.
+* Added details to behavior descriptions.
+* Expanded the corpus with hand-curated samples, focusing on behaviors without representative malware.
+* Defined [Attack Flows](https://github.com/center-for-threat-informed-defense/attack-flow/tree/main/corpus) for [Shamoon](https://github.com/MBCProject/mbc-markdown/blob/Lauren-malware-corpus/xample-malware/shamoon.md) and [SearchAwesome](https://github.com/MBCProject/mbc-markdown/blob/Lauren-malware-corpus/xample-malware/searchawesome.md), which reference MBC behaviors.
+* Defined a [CACAO](https://github.com/oasis-tcs/cacao) playbook for Locky Bart, which references MBC behaviors (will be submitted to the CACAO example repo soon).
+* Continued MBC website development. The website is slated to go live in the fall.
+
+MBC 3.0 will be released when the updated STIX 2.1 representation is finished and will include the changes outlined in recent newsletters.
+
+Please post questions or comments in [Discussions](https://github.com/MBCProject/mbc-markdown/discussions) on GitHub or email us at mbc@mitre.org. We'd love to get your feedback!
diff --git a/ynewsletters/README.md b/ynewsletters/README.md
index 39456b9..8cdfe7a 100644
--- a/ynewsletters/README.md
+++ b/ynewsletters/README.md
@@ -1,7 +1,10 @@
## Malware Behavior Catalog Newsletters ##
-September 2022
+
+June 2023
+
+March 2023
December 2022
-March 2023
\ No newline at end of file
+September 2022
\ No newline at end of file