diff --git a/matlab/README b/matlab/README
index 91c4a73ca1d7ca9e3090136e24f14dac673af4dc..0a79b3a4015a094b9cacd9652127df949b647d08 100644
--- a/matlab/README
+++ b/matlab/README
@@ -41,3 +41,6 @@ since then using svntag
 
 2019/06/28: tag 4_2 includes tag_3_10, 4_1 and 4_2 above: change default to LIUQE.M and introduced liuqe=1,2,3,11,12,13,21,22,23 or -1 as in GUIprofs and proffit and before mv to git
     svn cp https://spcsvn.epfl.ch/repos/TCV/gdat/trunk https://spcsvn.epfl.ch/repos/TCV/gdat/tags/gdat_v4_2 -m"includes tag_3_10, 4_1 and 4_2 in README file: change default to LIUQE.M and introduced liuqe=1,2,3,11,12,13,21,22,23 or -1 as in GUIprofs and proffit and before mv to git"
+
+2019/08/13: tag 4_2_1 which corresponds to git tag release-v4.2.1 (some fixes and new eqdsk source and jet and test improved)
+   svn cp https://spcsvn.epfl.ch/repos/TCV/gdat/trunk https://spcsvn.epfl.ch/repos/TCV/gdat/tags/gdat_v4_2_1 -m"synchronized with git tag release-v4.2.1 and now should use gittag for deployment in spc matlab crpptbx as well"