Enanta Pharmaceuticals Inc (ENTA)

[frontiers]

Rather early to call MRK's IDIX aquisition "excellent"

Maybe ... but MRK did in-house testing of 21437 to assure themselves before they agreed to the buyout.

you'd think if a $50+ PPS for ACHN was coming, perhaps those insiders wouldn't be selling those 11 million shares and counting at the current price

Hedge funds like RA or QVT which sold part of their holdings have investors they need to be cognizant of ... BTW, RA is still the largest shareholder with 13 MM shares and 3 MM call options at $5 ...