Numis, which has just celebrated its tenth anniversary, already has 22 corporate broking clients in the FTSE 250, including property group Savills, Domino’s Pizza and retailer Mothercare.
But Alliance Trust is its first official mandate on the roster of the UK’s 100 largest companies.
Numis will now act as joint corporate broker to the trust, alongside JP Morgan Cazenove.
The move is a significant one in the history of the firm, which began as a dedicated small-cap broking and advisory house and later started to make strides into the larger company space.
Numis’ head of corporate broking David Poutney said the appointment was “an important milestone” for the firm.
“This takes us further along the road towards our goal of becoming the leading corporate broker in London,” Poutney said.
Alliance Trust is led by Katherine Garrett-Cox, renowned for being one of just five women to run a FTSE 100 company.