Activist investor Knight Vinke Asset Management (KVAM) is today expected to issue a public statement signalling its dissatisfaction with what it regards as the underperformance of HSBC.
A statement by a single disgruntled minority shareholder - KVAM rarely takes stakes above 1 per cent - is not usually enough to frighten management.
But judging by the fund's record of engaging with companies in the past three years, HSBC can expect an uncomfortable period of scrutiny from investors and pressure to reform its strategy and management structure.
KVAM is led by Eric Knight. After business school and a spell as an investment banker in New York, Mr Knight set up KVAM in 2003 and turned it into a platform for activist successes at Royal Dutch Shell, VNU and Suez.
However, Mr Knight (47) cannot easily be pigeonholed as an old-style corporate predator agitating for a fast buck. He self-styles his brand of activism as "moral suasion" - an alternative method to seeking corporate change by takeover or through investor campaigns at company meetings.
Unlike some of his activist peers, Mr Knight often seeks to engage, and not confront, management to convince it to improve governance and restructure operations to create shareholder value.
KVAM typically invests in one large-cap company at a time, disseminating lengthy proprietary research in a target company to fellow activists, board members and financial analysts.
It is this approach that Mr Knight will almost certainly employ in the forthcoming weeks and months in a self-styled "constructive dialogue" with HSBC.
Mr Knight's success and tactics have attracted the support of a wider array of investors, many of whom entrust him with fronting a public battle.
Many institutional investors and pension funds lack the resources or confidence to take on the corporate establishment, so they have taken to encouraging Mr Knight's campaigns from behind the scenes.
As a result, KVAM - whose flagship fund recently passed $1.5 billion (€1.1 billion) in assets - punches way above its weight.
In 2004, Mr Knight successfully urged Royal Dutch Shell to abandon its dual British-Dutch structure in spite of owning a stake of just 0.03 per cent.
KVAM counts on the support of Calpers, the giant activist Californian state pension fund, which is its biggest financial backer.
At the beginning of the year, HSBC seemed a prime target for shareholder activism.
The banking group, which had grown into the world's fourth-largest financial institution through a series of audacious acquisitions, seemed to have lost its way.
HSBC had just issued the first profits warning in its modern history, the result of a foolish bet on US subprime mortgages that had prompted investors to question the bank's strategy and its ability to manage far-flung operations.
Eight months on, however, HSBC appears to have answered many of these criticisms.
The bank has moved quickly to stem the losses in the United States, and has moved to refocus the investment bank to concentrate on products and parts of the world where it enjoys a competitive advantage.
