Roth-Stern did not disclose the value of its bid or any other details.
Since half of Whitbread's offer for the pubs is in stock, the fall in its share price further lowered the value of its bid.
The amendment will raise the value of Zell/Chilmark's bid by $20 million, to $240 million.
That reduced the value of its stock-and-cash bid to $26.9 billion from $35.9 billion.
CSX has merely replaced the lost value of their initial bid.
And because of the way its offer is structured, any price rise increases the value of its bid.
The developer estimated that the value of his original bid was worth $329 million because he would build a larger, more modern railyard.
First Bank System's stock has since risen, increasing the value of its bid for First Interstate to $10.5 billion, or $137.80 a share.
For Pacific Century, however, the more pressing challenge will be preserving the value of its bid.
That drop will reduce the value of its bid to about $26.5 billion, a decline of about $500 million from the time the deal was announced.