Mega-merger fever is back seven years after the financial crisis, with the blockbuster buyout of British brewer SABMiller by Budweiser-maker Anheuser-Busch InBev.

The merger is the third biggest in corporate history after two huge telecoms tie-ups. Here is the all-time list of the top five mergers, according to Dealogic data service:

1. The world's biggest merger and acquisition deal remains British telecom company Vodafone's purchase of Germany's Mannesmann for $172 billion including debt, in 1999.

2. In 2013, Vodafone sold US telecoms giant Verizon its 45-percent stake in their joint venture Verizon Wireless for $130.1 billion.

3. The AB InBev buy-up of SABMiller on Tuesday is valued at $122 billion by Dealogic in a calculation that includes debt.

4. In 2000, the AOL-Time Warner merger at $112.1 billion came to symbolise the excesses of the first dot-com boom. The merger ultimately turned out to be a flop and the two companies split in 2009.

5. US drug company Pfizer in 1999 acquired rival Warner Lambert for $111.8 billion in stock and debt. The New York-based giant would become the world's biggest pharmaceutical company soon after.