trying to make sense of nabi sp ex dividend

Can anyone come up with a valid explanation as to why the NABI SP has not dropped since 26th October and certainly since the announcement yesterday of the actually dividend of $1.108 per share?

Anyone who has bought NABI after 26th October, cannot claim the dividend.

Closing prices for NABI have been:
Oct 26 $1.81
Oct 31 $1.71
Nov 1 $1.69
Nov 2 $1.70
Nov 5 $1.75

After the $1.81 close on Oct 26, we should have noticed a significant drop of at least $1, but we haven't.

There is talk that either:

- the NABI price has strengthened by about $1 since the dividend in recognition (finally) of the strength of the new entity.

- there is also talk of maybe the SP being falsely propped by those with a vested interest.

I don't really buy either explanation. Surely there is some technical factor that has not been explaned to us.

Anyone?