The 2026 SpaceX acquisition of xAI at $250 billion stands as the largest M&A deal in history, surpassing the telecom megamergers of the early 2000s.
Quick answer: 1. SpaceX acquires xAI, 2. Vodafone acquires Mannesmann, 3. AOL acquires Time Warner, 4. Verizon acquires Vodafone's stake in Verizon Wireless, 5. Anheuser-Busch InBev acquires SABMiller, 6. AT&T acquires Time Warner, 7. Dell acquires EMC, 8. Pfizer acquires Wyeth, 9. Bayer acquires Monsanto, 10. Praxair merges with Linde.
Mergers and acquisitions shape the corporate landscape, with the largest deals redefining entire industries. From the telecom frenzy of the late 1990s to the tech and AI megadeals of the 2020s, the biggest transactions have involved some of the world's most valuable companies. This list ranks the ten largest mergers and acquisitions in history by their nominal transaction value in US dollars. The figures represent the total value of the deal at announcement, including any debt assumption, as reported by the companies and verified by financial data sources.
In February 2026, SpaceX acquired xAI in a landmark $250 billion deal, creating the world's most valuable private company. The acquisition combined SpaceX's space and satellite infrastructure with xAI's advanced artificial intelligence capabilities, forming a vertically integrated AI and space technology powerhouse.
The $202.8 billion hostile takeover of German industrial and telecom conglomerate Mannesmann by UK-based Vodafone AirTouch in 1999-2000 was the largest M&A deal in history for two decades. It created the world's largest mobile telecom company and epitomised the dot-com era telecom consolidation frenzy.
The $181.6 billion merger of AOL and Time Warner in 2001 was the largest media merger in history, combining the world's largest internet service provider with the world's largest media company. It ultimately proved one of the most disastrous mergers, resulting in massive write-downs as the dot-com bubble burst.
In 2013, Verizon Communications acquired Vodafone's 45% stake in Verizon Wireless for $130 billion, gaining full control of the largest US mobile carrier. It was the third-largest deal in history and the largest ever in the telecommunications sector not involving a full merger of equals.
The $107.4 billion acquisition of SABMiller by Anheuser-Busch InBev in 2016 created the world's largest brewing company, controlling nearly 30% of the global beer market. The deal united iconic brands such as Budweiser, Stella Artois, Miller, and Pilsner Urquell under one corporate umbrella.
In 2018, AT&T acquired Time Warner for $85.4 billion after a protracted legal battle with the US Department of Justice. The deal combined AT&T's distribution network with Time Warner's content — including HBO, CNN, Warner Bros., and Turner — creating a media and telecom conglomerate.
The $67 billion acquisition of EMC by Dell in 2016 was the largest-ever technology merger at the time. The deal combined Dell's PC and server business with EMC's enterprise storage and data management portfolio, creating a giant in enterprise IT infrastructure under the Dell Technologies umbrella.
In 2009, Pfizer acquired Wyeth for $64 billion in a cash-and-stock deal that diversified Pfizer's portfolio beyond its flagship drug Lipitor, which was facing patent expiration. The acquisition added Wyeth's vaccines, biologics, and animal health businesses to Pfizer's pipeline.
In 2018, German pharmaceutical and life sciences company Bayer acquired US agrochemical giant Monsanto for $63 billion. The deal combined Bayer's pharmaceutical portfolio with Monsanto's seed and pesticide business, creating the world's largest agricultural company. The merger faced significant legal and regulatory challenges over glyphosate-related claims.
The $61 billion merger of equals between US-based Praxair and Germany's Linde in 2018 created the world's largest industrial gas company by revenue and market share. The combined entity operates under the Linde brand and supplies gases to industries ranging from healthcare to manufacturing and aerospace.
| # | Name | Deal value | Acquirer | Target | Year announced | Industry |
|---|---|---|---|---|---|---|
| 1 | SpaceX acquires xAI | $250 billion | SpaceX | xAI | 2026 | Technology / AI / Space |
| 2 | Vodafone acquires Mannesmann | $202.8 billion | Vodafone AirTouch (UK) | Mannesmann (Germany) | 1999 | Telecommunications |
| 3 | AOL acquires Time Warner | $181.6 billion | AOL (United States) | Time Warner (United States) | 2001 | Media / Internet |
| 4 | Verizon acquires Vodafone's stake in Verizon Wireless | $130 billion | Verizon Communications (United States) | Vodafone's 45% stake in Verizon Wireless | 2013 | Telecommunications |
| 5 | Anheuser-Busch InBev acquires SABMiller | $107.4 billion | Anheuser-Busch InBev (Belgium) | SABMiller (UK) | 2016 | Beverages / Brewing |
| 6 | AT&T acquires Time Warner | $85.4 billion | AT&T (United States) | Time Warner (United States) | 2018 | Telecommunications / Media |
| 7 | Dell acquires EMC | $67 billion | Dell (United States) | EMC Corporation (United States) | 2016 | Technology |
| 8 | Pfizer acquires Wyeth | $64 billion | Pfizer (United States) | Wyeth (United States) | 2009 | Pharmaceuticals |
| 9 | Bayer acquires Monsanto | $63 billion | Bayer (Germany) | Monsanto (United States) | 2018 | Agriculture / Life Sciences |
| 10 | Praxair merges with Linde | $61 billion | Praxair (United States) / Linde (Germany) | Merger of equals | 2018 | Industrial Gases / Chemicals |
Deals are ranked by their announced transaction value in US dollars — the total consideration including equity, cash, and assumed debt. Only completed or announced mergers and acquisitions are included; proposed deals that were withdrawn or blocked are excluded. Figures are nominal (not adjusted for inflation). Rank 1 is the largest deal by value. Data is drawn from Wikipedia's List of largest mergers and acquisitions, cross-checked against Bloomberg and Reuters financial reporting.
The largest M&A deal in history is SpaceX's acquisition of xAI in 2026, valued at $250 billion. It surpassed the previous record-holder, Vodafone's $202.8 billion acquisition of Mannesmann in 2000.
Deal values can vary depending on whether they include assumed debt, the premium paid over market price, and whether the figure is adjusted for inflation. This list uses nominal announced values including assumed debt.
Telecommunications, technology, media, and pharmaceuticals have historically seen the largest deals. The top five deals include two telecom mergers, two media/tech mergers, and the 2026 SpaceX-xAI combination.
No. The figures are nominal — the actual dollar value at the time of announcement. An inflation-adjusted ranking would place older deals higher; for example, the 1999 Vodafone-Mannesmann deal would be worth approximately $380 billion in 2026 dollars.