That is interesting. Assuming you are right that the stock is moving on approval news being leaked from the FDA, I would think there would be a negative reaction in TEVA's stock yet no movement there. Perhaps there are no insider trading laws in India and Natco makes the perfect venue for insider trading.
Nevertheless, the longer the FDA takes, the higher the odds for more than one generic being approved and diminished jump in valuation for MNTA. There is also the possibility that TEVA is negotiating with Sandoz but Natco being in the picture would make negotiations useless