The group, which yesterday confirmed that it had rebuffed the entrepreneur's advances at a meeting on Tuesday evening, is facing discontent over the roles of Sir Ian Prosser and Richard North.
Sir Ian is due to remain chairman of the hotel business until the end of the year, although some shareholders are calling for him to step down immediately.
Mr North's move from group finance director to hotels chief executive is also causing concern among investors.
Six Continents (6C) does not appear to be prepared to countenance any management changes, although one analyst said the group would have to "think outside the box to stand any chance of surviving a hostile bid situation". A spokeswoman for 6C said last night: "The details of the two management teams are well known and they are the teams that will take the two companies through to demerger and beyond."
At Tuesday's meeting, Mr Osmond is understood to have given a broad outline of his plan to launch an all-paper bid through Capital Management & Investment worth about 650p a share -equivalent to Pounds 5.64 billion, or more than Pounds 7 billion including debt -with a partial cash alternative of between Pounds 1 billion to Pounds 2 billion.
According to Mr Osmond, the 6C directors present -Sir Ian, Mr North and chief executive Tim Clarke -said they were unwilling to consider anything other than a firm offer and advised him that they had said exactly the same thing to a number of other potential bidders, thought to include Kohlberg Kravis Roberts, Blackstone Group, Starwood Hotels and CVC Capital Partners.
