This is a bit behind as it happened over the break:
The “tobacco plain packaging” legislation became law last December and, as you will recall, Philip Morris Asia has initiated an arbitration proceeding under the Australia-Hong Kong Investment Treaty.
Australia filed its “defence” late in December, alleging that Philip Morris Asia bought the assets in question after the Government’s plans were known and so hasn’t lost any value:
Prof. Davison has a typically wry report
Philip Morris’ complaint and Australia’s “defence” are available via here.