Liontrust joint investment directors Jeremy Lang and William Pattisson have resigned from the boutique fund house.
Analyst Cazenove says the move is "a remarkable development by any standards".
A Cazenove broker note says: "Quite why these key managers should have announced their resignation while the company is still in talks with potential acquirers is not clear but can hardly be conducive to a successful outcome, in our view.
"Whether a new manager could be found with sufficient standing and credibility to appeal to consultants, but insufficient self belief in their own ability to be willing to run money according to someone else's strategy is unclear.
"We are not changing estimates at this stage, but in due course it seems likely that we will have to assume material outflows."
Authors of The Lang Approach (if a company surprises on the upside, it is likely to do so again), The Value Dynamic (mean reversion of high yield stocks) and Large Cap Process (not selling companies with rising expectations too soon), the founding managers, were rewarded to the tune of £3.8m each in the year to March 2008 as shares of the management fee income from their funds, they also received large initial equity holdings and substantial minority shares in the European team business.IFAonline
£92bn transferred since 2015
Achievements, charity work and other happy snippets
Since first announcement