Arbitrary, unreasonable and/or discriminatory measures
Umbrella clause
http://globalarbitrationreview.com/news/article/33072/%20water-utility-taps-estonia-damages/ (requires subscription)
www.iareporter.com/articles/20140513_1 (requires subscription)
http://www.iareporter.com/articles/20141015 (requires subscription)
http://tallinnavesi.ee/en/Investor/663-AS-Tallinna-Vesi-teavitas-Eesti-Vabariiki-rahvusvahelise-lepingu-rikkumisest-tulenevast-voimalikust-noudest
http://news.err.ee/v/economy/f341c535-efb4-4521-9653-b280ee213aa4
http://www.iareporter.com/articles/20140513 (requires subscription)
https://www.iareporter.com/articles/analysis-drymer-chaired-tribunal-unanimously-rejects-intra-eu-objection-and-see-control-by-minority-shareholder-but-arbitrators-disagree-on-whether-or-not-estonia-breached-claimants-legitim (requires subscription)
https://tallinnavesi.ee/en/investor/regulation/icsid-materials/
https://www.squirepattonboggs.com/en/news/2019/06/squire-patton-boggs-secures-victory-for-the-republic-of-estonia-in-us100-million-investment-dispute