A couple of years ago we were working with a systems integrator who had a great offer from a large British suitor.  We accepted the offer, and continued through negotiation of the Definitive agreement.  On closing day, the buyer, their top three management staff, and their counsel all came from London for closing.  However, at the last possible moment, they made a major change to the deal.  We had negotiated a limitation of 20% of total deal price on all seller indemnifications.  We had agreed to indemnify the buyer very fairly, but, because such indemnifications included reps and warranties on uninvestigated environmental conditions, both on land and on certain building sites, we felt the "cap" on those exposures was an important cap. (Exposure was unlikely – but still possible.)  Although it is common for international buyers to resist such caps (limitations are common in the US, but rare in Europe) – we had discussed the matter in detail and had clearly agreed with the buyers upon a fixed ceiling amount.  (If that had not been agreed upon, we would not have accepted the offer). 

When the British buyers came to closing, they brought a Definitive in which they had removed our "cap."  (They said their Board had approved the transaction, but only with removal of the cap on indemnifications.)  We told them we were sorry for their long trip, but such change was not acceptable, and we would now terminate the letter of intent and return to other buyers.  They spent the next half-day on the phone with executives and Board members from their home – and they did go ahead and close, next day, with our "cap" reinstated.