Just did some calculations and it looks like back dividends are something close to:
0.0003412014 per Mining or Purchase
0.002000772 per Selling or Purchase
As of October 25th there were 163054 "Effective Units" outstanding. That means DMS is about 382 BTC behind on dividend payments.
Are you sure?
IIRC there was a little more than 100 BTC in the wallet, plus the cyphermine bonds... or were those bonds worth almost 300 BTC?