The Biggest Acquisitions In History Since 2015: Insights and Outcomes

Over the past decade, the business world has witnessed some of the biggest acquisitions in history. Many are worth tens of billions of dollars. These high-stakes deals don’t just grab headlines; they reshape industries, shift market dynamics, and influence investor confidence.

However, not every merger reaches the finish line. Regulatory hurdles, shareholder concerns, and operational complexity often hinder progress. Even when deals do go through, they require tight coordination across legal, finance, and strategy teams.

For companies navigating these high-stakes scenarios, mergers and acquisitions (M&A) software is essential. These platforms streamline workflows, coordinate diligence, and help legal, finance, and strategy teams stay aligned throughout the integration process.

In this article, we look back at the most significant acquisitions from the past 10 years. Beyond just the price tags, we’ll unpack why they mattered. 

The biggest mergers and acquisitions in history at a glance

Below is a brief overview of the biggest acquisition noted in the pages of history. 

Biggest acquisitions: Value and outcome

These mega-deals didn’t just exchange sums of money; they transformed the market and often prompted further consolidation. Below, we break down each of the top acquisitions, highlighting why they mattered. 

1. Dow Chemical + DuPont (2015): A $130 billion chemical mega‑merger

• Value: $130 billion in an all-stock merger of equals.
• Industry: Chemicals in agriculture, materials, and specialty products
• Outcome: Formed DowDuPont, which later split into three companies: Dow Inc., DuPont, and Corteva

In late 2015, Dow Chemical Co. and DuPont agreed to an all-stock “merger of equals” worth about $130 billion.  The merger was strategic: after joining forces, DowDuPont planned to break apart into three separate businesses focusing on agriculture, materials (plastics), and specialty chemicals. 

This deal faced immense regulatory scrutiny, especially around the big agrichemical division, but the companies were able to pull it off. By 2019, DowDuPont split into Corteva, based in agriculture, and DuPont got into specialty production. 

2. Heinz and Kraft Foods (2015): A $100 billion food industry merger

• Value: $100 billion
• Industry: Food and beverage (Consumer packaged goods)
• Outcome: Formed Kraft Heinz Co., now one of North America’s largest food companies.

This wasn’t a traditional buyout of one rival by another. Instead, famed investor Warren Buffett and 3G Capital orchestrated a plan: Heinz (which 3G/Buffett had taken private in 2013) would acquire Kraft, with Kraft shareholders getting a big cash payout ($10 billion) and 49% of the new entity for the merger into The Kraft Heinz Company. 

The merger of H.J. Heinz Co. and Kraft Foods Group was valued at around $100 billion. For consumers, it meant a pantry full of iconic brands, such as Heinz, Kraft, Oscar Mayer, Philadelphia, etc. The combined Kraft Heinz became one of the largest food and beverage companies in the world overnight. 

However, merging wasn’t just about bragging rights; it’s also about cutting costs to stay profitable. Indeed, soon after, Kraft Heinz slashed expenses, which unfortunately meant some jobs were cut. 

3. Anheuser-Busch InBev and SABMiller (2016): A $107 billion “megabrew” deal

• Value: $107 billion
• Industry: Beverage 
• Outcome: Anheuser-Busch (AB) InBev became the world’s largest brewer, but had to divest brands to appease regulators.

After the $107 billion takeover of SABMiller, AB InBev owned nearly 30% of the world’s beer. For context, Budweiser, Stella Artois, and Corona makers (AB InBev) acquired SABMiller's extensive portfolio of beers, which included Miller, Castle, and Foster’s. 

But regulators only approved the deal on the condition that SABMiller’s stake in MillerCoors (its American joint venture) be sold off to settle antitrust concerns. They thought the combined company would have too significant a share of the U.S. beer market.

Considering this portfolio, if you have raised a pint in the past few years, there’s a good chance the brewery traces back to these combined giants. 

4. BAT and Reynolds American (2017): A $49 billion big tobacco consolidation

• Value: $49 billion
• Industry: Tobacco
• Outcome: British American Tobacco (BAT) acquired the remaining 58% of Reynolds American that it didn’t already own, bringing Newport, Camel, and Pall Mall cigarettes all under BAT.

In 2017, British American Tobacco, maker of Lucky Strike and Dunhill, decided it wanted full control of Reynolds American, the U.S. company behind Newport, Camel, and Pall Mall. BAT already owned 42% of Reynolds from a prior deal, but it paid $49 billion to buy out the rest of Reynolds American. This deal stands out as one of the largest in “sin industries” and made BAT the world’s most prominent publicly traded tobacco firm. 

If you’re a smoker in the U.S., this likely had minimal visible impact on your day-to-day – Newport and Camel packs didn’t change overnight. However, behind the scenes, a lot did change: an American tobacco icon, Reynolds, which itself was a consolidation of R.J. Reynolds and Brown & Williamson years earlier, became fully owned by a British company. BAT acquired Newport, the best-selling menthol cigarette in the U.S.

This gave it full access to a large share of the market it had previously only partly benefited from through its minority stake.

The deal did remove Reynolds as a standalone American company, leaving Altria (Marlboro’s parent) and BAT/Reynolds as the two giants in U.S. cigarettes, plus some smaller players. 

5. AT&T and Time Warner (2018): Over $85 billion telecom–media takeover

• Value: $85.4 billion
• Industry: Telecom and media
• Outcome: AT&T acquired Time Warner Inc., the owner of HBO, Warner Bros, CNN, etc., forming WarnerMedia but ultimately spun it off in 2022 after challenges.

This deal was the classic case of a telecom giant wanting to own premium content. It was announced in 2016 and closed in 2018. 

As a media consumer, you might have cheered the idea of your cable/internet provider being under the same roof as HBO’s Game of Thrones. The U.S. Department of Justice, however, was less enthused. They sued to block the deal, concerned AT&T might use Time Warner content to unfairly raise prices on rivals. AT&T ultimately won in court, and the merger closed, creating a new “WarnerMedia” division under AT&T. 

AT&T promised that combining distribution and content would be beneficial. But things didn’t go as planned: by 2021, AT&T was struggling with debt and strategy, so they decided to spin off WarnerMedia. In 2022, WarnerMedia merged with Discovery, Inc., effectively undoing AT&T’s big bet. 

6. United Technologies and Raytheon (2019): A $121  billion aerospace and defense merger

• Value: $121 billion (all-stock merger)
• Industry: Aerospace and defense
• Outcome: Created Raytheon Technologies, now one of the world’s largest defense contractors.

When United Technologies Corp. merged with Raytheon Co. in 2019, it formed a new aerospace giant valued at approximately $121 billion. If you follow defense news, you know this deal instantly made the new company, Raytheon Technologies, the world’s second-largest defense contractor, trailing only Boeing at the time, the largest then. 

The combined company brings together everything from Pratt & Whitney jet engines and Collins Aerospace avionics (from UTC) to Raytheon’s missiles and radar systems. Regulators gave the merger a green light in 2020. 

7. Saudi Aramco and SABIC (2020): A $69.1  billion petrochem megadeal

• Value: $69.1 billion for 70% stake
• Industry: Petroleum and petrochemicals
• Outcome: Saudi Aramco purchased a majority stake in SABIC from Saudi Arabia’s sovereign wealth fund, integrating oil production with downstream chemicals.

In 2020, Saudi Aramco, known as the world’s most valuable oil producer, took a significant step downstream by acquiring a 70% stake in Saudi Basic Industries Corp. SABIC for $69.1 billion. 

This wasn’t an international acquisition; it was essentially one Saudi state-run giant buying another. But for the global petrochemical market, it was big news. By joining forces with Aramco, the idea was to integrate oil and chemicals better. Aramco pumps crude oil and natural gas, and SABIC turns hydrocarbons into valuable chemicals and plastics. For Saudi Arabia’s economy, it meant moving beyond just exporting crude to exporting higher-value products. 

This deal signaled Aramco’s downstream ambitions. It occurred around the same time Aramco was going public in a record-breaking IPO. 

8. PSA Group and Fiat Chrysler (2021): A $52B auto merger of equals

• Value: $52 billion combined market value
• Industry: Automotive
• Outcome: Formed Stellantis in 2021, creating the world’s fourth-largest automaker, and brought brands like Jeep, Ram, Peugeot, and Fiat under one company

In the automotive world, 2021 saw the birth of Stellantis, a company name you might not recognize, but whose car brands you certainly will. Stellantis was formed by the 50-50 merger of PSA Group, the French automaker behind Peugeot, Citroën, and Opel,  and Fiat Chrysler Automobiles (FCA), which is the parent of Fiat, Chrysler, Jeep, Dodge, Ram, etc. This transatlantic tie-up was valued at around $52 billion at merger time. 

The merger helped fill geographic gaps: PSA was strong in Europe but absent in the US; FCA was strong in North America (with Jeep and Ram) but weaker in Europe aside from Fiat. Combined, they get a better balance globally. Culturally, it merged French and Italian/American automotive legacies. 

9. S&P Global and IHS Markit (2022): A $140 billion fintech data merger

• Value: $140 billion
• Industry: Financial information and analytics
• Outcome: The deal broadened S&P’s data offerings, from bond ratings and indices to market intelligence on energy, automotive, etc.

S&P Global, known for credit ratings, indices, and data, completed its $140 billion merger with IHS Markit in early 2022. If you’re an investor or work in finance, this merger probably impacted you. For example, the data feed behind your Bloomberg might now be coming from a combined S&P/IHS source, or the index underlying an Exchange-Traded Fund (ETF) might be from S&P Dow Jones, strengthened by IHS’s analytics. 

Regulators did make S&P sell off a few overlapping pieces. For example, IHS’s base chemicals data business and some of S&P’s leveraged loan data, to prevent too much concentration in specific niche data markets. The combined company retained the S&P Global name. 

10. Microsoft and Activision Blizzard (2023): A $68.7 billion level-up in gaming

• Value: $68.7 billion
• Industry: Technology (video game development and publishing)
• Outcome: Microsoft acquired gaming publisher Activision Blizzard, adding blockbuster franchises like Call of Duty, Warcraft, and Candy Crush to Xbox’s portfolio.

In January 2022, when Microsoft announced plans to buy Activision Blizzard, gamers everywhere took notice. After nearly 21 months of regulatory scrutiny, Microsoft completed the $68.7 billion acquisition in October 2023. This is one of the most significant tech acquisitions ever and certainly the biggest in video game history. 

Regulators in the US and UK initially raised concerns. For instance, would Microsoft make Call of Duty exclusive, potentially harming PlayStation? Or would it stifle cloud gaming competition? Microsoft made commitments, like ensuring Call of Duty stays on PlayStation for years and agreeing to some cloud-gaming concessions, which helped get the deal approved. 

11. ExxonMobil and Pioneer Natural Resources (2024): A $59.5 billion oil megadeal

• Value: $59.5 billion (all-stock)
• Industry: Oil and gas
• Outcome: The acquisition increased Exxon’s U.S. oil output.

In October 2023, oil giant ExxonMobil announced a deal to acquire Pioneer Natural Resources, a dominant player in the Permian Basin shale oil region, for $59.5 billion in an all-stock transaction. The deal closed in early 2024 after regulatory clearance, marking Exxon’s largest acquisition since merging with Mobil in 1999. 

For the U.S. oil industry, it was a sign of consolidation in shale. On an environmental note, some critics raised eyebrows as Exxon pivoted from talking up low-carbon initiatives back to making a massive oil investment. However, ExxonMobil shared its plan to achieve net-zero while applying its industry-leading technologies for monitoring, measuring, and addressing fugitive methane to reduce the combined companies’ methane emissions.

From a consumer perspective, more supply from an efficient producer helps moderate fuel prices, but global oil pricing is complex.

Pending and failed acquisitions and mergers to watch during and after 2025

Not every proposed acquisition sails through smoothly. Some are still underway, facing regulatory or shareholder approval, while some have died striving to take those approvals. Here are some that made headlines but didn’t make past the finish line:

• Kroger and Albertsons (announced in 2022, $24.6 billion): A proposed merger of two top U.S. grocery chains. If approved, it would create a supermarket giant, but regulators are scrutinizing it for potential impacts on grocery prices and competition. The deal officially died on December 11, 2024, after the judges' rulings.
• Adobe and Figma (announced in 2022, $20 billion): In the tech/tools space, Adobe’s bid to buy Figma, a collaborative design software startup, drew a lot of attention. The deal’s steep price and the fact that Figma was an emerging rival have U.S. and EU regulators on guard, reviewing whether this would stifle competition in design software. On December 18, both companies entered into a mutual agreement to terminate their previously announced merger agreement.
• JetBlue and Spirit Airlines (announced in 2022, $3.8 billion): A smaller deal by dollar value, but big in air travel buzz. JetBlue’s attempt to acquire ultra-low-cost carrier Spirit has been turbulent. The DOJ sued to block it, citing concerns that eliminating Spirit could lead to higher prices for budget flyers. On March 4, 2024, JetBlue announced the termination of the merger agreement initially proposed. JetBlue paid Spirit $69 million, and the termination resolved all outstanding matters related to the transaction, under which any claims between them were mutually released.

• Pfizer and Allergan (2016, $160 billion): This would have been the largest pharma deal ever, effectively Pfizer “buying” Allergan in a complex merger to move its domicile to Ireland. The deal was scrapped at the last minute when U.S. authorities changed tax rules to curb tax inversions. So, Allergan never joined Pfizer. Instead, as we saw, Allergan later went to AbbVie.
• Zoom and Five9 (2021, $14.7  billion): Video-conferencing software Zoom agreed to buy cloud contact center firm Five9, but Zoom’s stock dropped, and Five9 shareholders rejected the all-stock deal. Also, U.S. regulators had signaled a potential national security review because of Zoom’s ties to China, which didn’t help. The merger was called off, showing even in tech, not all high-flyers pair up successfully.

Acquisitions involve intense due diligence. Some deals go through and turn out to be good, while some land flat on the negotiation table. 

Strategizing growth in a saturated market

These deals weren’t just about big numbers; they were strategic moves to gain market share and expand into new verticals. It suggests that consolidation isn’t slowing down. If anything, it’s becoming the go-to strategy for growth in a saturated market.

On the other hand, not every deal delivers on its promise. Some acquisitions led to bloated operations or regulatory backlash. Others, however, have unlocked real innovation and value.

The pace of consolidation is unlikely to slow. Rising competition, technological disruption, and geopolitical uncertainty will keep pushing companies toward mergers and acquisitions as a core growth strategy. The question isn’t whether the next mega-deal will happen — it’s which industry it will disrupt first, and whether it will live up to its billion-dollar promise.

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