Brunswick was brought in last week to work alongside Amersham’s retained PR adviser, Financial Dynamics.
Amersham declined to comment on why it had brought in Brunswick to work on the transaction.
FD managing director and head of life sciences David Yates said the firm has been working with Brunswick on the deal, which was made public last week.
Brunswick partner John Coles is leading a team of six on the deal, which also includes partner Louise Charlton.
GE hired Tulchan Communications to work on the Amersham deal on its behalf several months ago.
Founder Andrew Grant is leading the account for Tulchan and reports to Louise Binns, GE general manager for media and PA in Europe, the Middle East and Africa.
Under the deal, which is GE’s first acquisition of a UK- listed company, Amersham will be combined with GE’s medical businesses and renamed GE Healthcare Technologies. The new company will remain based in the UK.