Booth, who revealed the news in an announcement to his staff earlier this week, is understood to be considering numerous offers about his next move, which is likely to include the launch of a new venture in the UK digital marketing sector.
Tangozebra was bought by US-owned DoubleClick from Media Square for £15 million in March. It was founded by Booth and James Barrs in 1996 and became one of the few UK-owned digital ad businesses to compete with the US giants.
Booth said of his departure: "Following the successful initial integration phase and the coming together of the two businesses into one office shortly, I will be leaving Tangozebra/DoubleClick in the summer to explore new opportunities."
Since the merger, DoubleClick has itself become subject to a £3.1bn takeover bid by Google.