One market source close to the process said the account could be worth more than £100,000.
Mainland has handled PR for SGAM since 1998, shortly after the group was set up by former Morgan Grenfell fund manager Nicola Horlick. Mainland founder Neil Mainland has a close business relationship with Horlick, who left SGAM in 2003.
SGAM head of marketing Mik Bates declined to comment on the review and would not say whether the fund manager had invited Mainland to repitch.
Mainland declined to comment.
Last November, Horlick hired Mainland to promote her new fund management venture, Bramdeen Asset Management (PRWeek, 5 November 2004).
Last year, Horlick's successor as chief executive at SGAM,Keith Percy, set out an ambitious plan to double the company's assets under management over a five-year period.
Percy said SGAM would increase its portfolio from £7.5bn to £15bn.