Incumbent agency Lowe is still in the running to retain the account, pitching with fellow Interpublic Group agencies to win the work, which as well as the global advertising account also includes media and direct marketing.
The two other contenders are a WPP Group bid, led by J Walter Thompson, and a pitch from Omnicom Group, headed by BBDO Worldwide. Publicis Groupe was cut from the shortlist in February.
With Publicis out of the race, the media business held by ZenithOptimedia will move even if nothing else does.
The expectation had been that a decision would be made in early May, but reports say that a decision may now not come until June.
HSBC is conducting the review, its first in five years, to improve cost effectiveness and the consistency of brand strategy. The bank has already said that it will retain the slogan "the world's local bank".
The review is being overseen by general manager of marketing Peter Stringham, a former president and chief executive of the Omnicom-owned BBDO Canada.
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