Yeah, that dragged on a bit. Simple answer is:
Post# of 36532
If you bought 100 shares and cost was $1000, your cost basis is $1000/100 = $10/share. Once you received the 20 for 1 dividend, your cost basis is now $1000/2100 = $0.48 per share.
The only question is if you can assign all the cost to the first 100 shares @ $10/share. If so, then the rest of the 2000 shares have a cost basis of $0. I think the first in, first out rules are still in effect, but am not sure if that applies to the dividend shares.
Either way, whatever your selling price for the entire lot of shares, you can only deduct $1000 against the final selling price.
The new dividend shares (NGO) will all have a cost basis of $0. Since as Joe said, they are being given to you for your ownership of GNBT.
IRS always gets its money. Period. (to quote a well known CEO!).