The Beijing-based agency was founded in 2007 and specialises in online media buying, online PR, communcations strategy and website design.
Its clients include China Mobile Communications Corporation and the Industrial and Commercial Bank of China.
According to Aegis, eLink's gross assets at the end of last year were £3m. The transaction is subject to regulatory approval and expected to close in the second quarter.
The move is part of Aegis’s wider strategy to raise its digital profile and capabilities in faster growing regions, such as China.
Last year, Aegis made more than 10 acquisitions, including MediaVest Manchester, Lithuanian media agency, Creative Media Services UAB, and Canadian social media moderation company, ICUC Moderation Services.
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