Amarin Corp Plc (AMRN)

[sts66]

Please give me just one reason why a "private" buyer might want to do such a thing.

To get a piece of the pie before big news comes out, for instance NCE designation? That NAVB private placement was done a month before they received FDA approval for Lymphoseek. Buying that many shares (!.5M) on the open market for a low-volume stock would have likely been much more costly than the behind the scenes arrangement they came up with. Not saying that's what's going on with AMRN and JPM, just mentioning it's a possibility.