Tether.to is a custodian service, priding itself upon being transparent at all times. To achieve this goal, the company makes their reserves balance sheet publicly available. It appears there is some cause for concern, though. Right now, there is a near-million dollar discrepancy between their fiat reserves and the number of tethers in circulation. A very unusual situation, that much is certain.
... read more: http://www.newsbtc.com/2017/03/21/tether-balance-sheet-unveils-large-discrepancy-usdt-usd-reserves/