Arbitrary, unreasonable and/or discriminatory measures
Full protection and security, or similar
Most-favoured nation treatment
National treatment
Indirect expropriation
Customary rules of international law
http://www.iareporter.com/articles/20110907_6 (requires subscription)
http://globalarbitrationreview.com/news/article/29691/czech-republic-sees-off-long-running-claim/ (requires subscription)
http://www.iareporter.com/articles/czech-republic-govt-releases-cache-of-bit-awards-strives-to-collect-costs-orders-and-currently-faces-eleven-pending-treaty-claims/ (requires subscription)