(Bloomberg) -- SoftBank Group International Chief Financial Officer Alok Sama will step down from his post, according to an internal memo seen by Bloomberg News.

He will remain a senior adviser at the company, according to the memo, which didn’t provide a reason for his departure. Sama led the execution teams for the $59 billion merger of Sprint and T-Mobile and the $34 billion acquisition of ARM Holdings Plc, among other deals, according to the memo.

Sama’s departure comes against the backdrop of management upheaval at the firm. SoftBank Group’s board has investigated who was behind a shareholder campaign seeking the ouster of two executives and whether the effort had any connections to company insiders, the Wall Street Journal reported last year, citing unidentified people familiar with the matter.

Sama will remain as a Softbank representative on boards including SB Energy and SoFi, according to the memo.

To contact the reporters on this story: Min Jeong Lee in Tokyo at mlee754@bloomberg.net;Pavel Alpeyev in Tokyo at palpeyev@bloomberg.net

To contact the editors responsible for this story: Divya Balji at dbalji1@bloomberg.net, Tim Smith, Jeff Sutherland

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