Eni S.p.A. (Italian pronunciation: [ˈɛːni]) is an Italian multinational oil and gas company headquartered in Rome. Considered one of the global supermajors, it has operations in 79 countries, and is currently world's 11th largest industrial company with a market capitalization of 68 billion euros (US$ 90 billion), as of August 14, 2013. The Italian government owns a 30.303% golden share in the company, 3.934% held through the state Treasury and 26.369% held through the Cassa Depositi e Prestiti. Another 2.012% of the shares are held by the People's Bank of China. The company is a component of the Euro Stoxx 50 stock market index.

The name "ENI" was initially the acronym of "Ente Nazionale Idrocarburi" (National Hydrocarbons Authority). Through the years after its foundation however, it operated in a large number of fields including contracting, nuclear power, energy, mining, chemicals and plastics, refining/extraction and distribution machinery, hospitality industry and even textile industry and news.

Eni constantly ranks among the top 100 on Fortune Global 500 list for largest companies by revenue. In 2016, the company holds the 65th place, a fall of 40 places from the previous year's 25th rank.

In terms of share capitalisation (the market value of shares), Eni is ranked sixth in comparison with the principal companies operating in the same sector: Exxon, Shell, Chevron, Total, BP, ConocoPhillips, Statoil, Anadarko, Apache and Marathon Oil.

In July 2017, the oil giant accepted responsibility for an oil spill affecting the Fylde coast of Blackpool in the United Kingdom.

Eni was founded and established by law in 1953 from an existing company, Agip, which was created in 1926 with the aim to explore for oilfields, acquire and commercialize oil and derivatives. In March 1953, Enrico Mattei was nominated Eni's Chairman.

Eni originally was an acronym for the company's full title Ente Nazionale Idrocarburi. After 1995, the meaning ceased to be relevant but the name was maintained.

In 1952 Eni chose its own logo, the six-legged dog, an imaginary animal symbolizing the sum of a car's four wheels and the two legs of its driver.

Starting in 1954, Eni acquired extensive exploration rights in North Africa, signing an agreement with the Egyptian government led by Nasser while providing an active and equal role for the crude producing countries through the establishment of joint ventures.

In 1957 Eni pushed for a similar agreement, known as the "Mattei formula", to be signed with Persian Shah Mohammad Reza Pahlavi and the National Iranian Company.

In 1960, during the Cold War period, Eni signed an agreement with the Soviet Union for the importation of Russian crude at very reasonable prices.

On 27 October 1962 Enrico Mattei died in an aircraft accident near Bascapè, on his way to Milan from Catania.

During the following years, Eni signed joint venture contracts with foreign companies to supply crude from Egypt to Iran and from Libya to Tunisia.

In 1963, Eni acquired a majority stake in Italgas.

In October 1973 after the Yom Kippur War and the embargo against the United States and the Netherlands agreed by OPEC members Arab countries, a serious oil crisis occurred, pushing Eni in need to consolidate its position in the international market by signing an agreement with Sonatrach, the Algerian state oil entity for natural gas supply.

In 1974 Eni signed an agreement with Libyan government, followed by further agreements with Egypt, Nigeria and Tunisia, while developing two new major oil discoveries in the British North Sea got on 1972.

During the mid-1970s Eni planned a major infrastructure for transporting natural gas over long distances by building a pipeline network of thousands of miles throughout Europe and the Mediterranean.

After the inauguration of the Trans-Mediterranean Pipeline connecting Algeria to Sicily through Tunisia, Eni signs a new agreement with Libya for the exploitation of Boùri, the biggest oilfield in the centre of the Mediterranean, and develops its international role within the oil industry.

In 1992 Eni became a joint stock company by Law Decree, and was listed to the Italian and New York Stock Exchange in 1995.

From 1995 to 1998 Eni put four share offers fully successfully, as 70% of its capital assets were sold to private shareholders.

As the price of oil collapsed in 1998 as other major companies Eni got to turn into a race through merges, international acquisitions, new explorations and the foundation of real super-companies.

Since 2000, Eni has been developing the Kashagan oilfield a major offshore discovery, along the Caspian Sea.

In 2005 the Blue Stream pipeline projected to supply gas from southern Russia to Turkey was inaugurated as a joint venture between Eni and Gazprom.

In 2007 Eni signed an agreement to conduct South Stream a feasibility study with Gazprom to import Russian gas into Europe across the Black Sea.

Activist asset manager Knight Vinke, who owns 1% of the outstanding shares of the company, begun pressuring Eni's management to operate a spin-off of Eni's gas activities. In its opinion this would solve the undervaluation of the company and release up to 50 billion euros ($70bn) of hidden value.

In 2010 Eni achieves key production milestone in Iraqi Zubair oil field.

After getting a licence in 2006 for the exploration of an offshore area in the north of Mozambique, known as Area 4, Eni announced several major natural gas discoveries between 2011 and 2012 such as Mamba South, Mamba North, Mamba North East, Coral 1.

In February 2014, ENI discovered oil at its DRC offshore block.

Since 2012 Eni has been selling off refining and marketing assets it owned in eastern Europe in order to increase profitability. By 2013 Eni already reduced its refining capacity by 13 percent. In May 2014 Eni agreed to sell their 32.5% share in Česká rafinerská a.s. (CRC), a refining company in Czech Republic, to MOL Group of Hungary.

In June 2014 the company signed an agreement with Sasol to acquire a 40% interest in a permit to explore 82,000-km offshore of South Africa's east coast.

In January 2015, Eni in collaboration with Vitol Energy signed a $7 billion contract with the government of Ghana. This agreement was reached in order to produce oil and gas at Cape Three Points in the Western Region of Ghana, in an attempt to enable Ghana meet its power and energy needs.

In August 2015 Eni announced the discovery of a huge gasfield off the coast of Egypt.

As exploration and reserve replacement being major drivers for the company, Eni boosts for production additions in its core oil field areas (North and Sub-Saharan Africa, Venezuela, Barents Sea, Yamal Peninsula, Kazakhstan, Iraq and the Far East). Eni has about 130 exploration and production subsidiaries, such as Eni Norge.

In 2012 Eni reported liquids and gas production for the full year of 1,701 kboe/d, this being calculated assuming a natural gas conversion factor to barrel equivalent, updated to 5,492 cubic feet of gas equal 1 barrel of oil from July 1, 2012.

During 2012 60 new exploratory wells were drilled, as 56 were drilled in 2011 and 47 in 2010. The overall commercial success rate was 40% (40.8% net to Eni) as compared to 42% in 2011 (38.6% net to Eni) and 41% in 2010 (39% net to Eni). In 2012 351 development wells were drilled as well, as 407 in 2011 and 399 in 2010.

In 2012, sales of natural gas were 95.32 bcm, down 1.44 bcm compared to 2011.

Eni's power generation sites are located in Ferrera Erbognone, Ravenna, Livorno, Taranto, Mantova, Brindisi, Ferrara and Bolgiano. In 2012, Eni's power generation was 25.67 TWh.
Overall Eni supplies 2,600 customers including large companies, power generation companies, wholesalers and distributors of natural gas for automotive use. Residential users are 7.45 million and include households, professionals, small and medium size enterprises, and public bodies located all over Italy and 2.09 million customers in European Countries. International sales include Iberian Peninsula, Germany, Austria, Benelux, Hungary, UK/Northern Europe, Turkey, France markets.

Eni's electricity generation sites in Italy, as of January 2010, are the following:

Eni is the leader operator in refining and marketing of petroleum products in Italy.
Eni is engaged in retail and wholesales activities in Central-Eastern European countries also (Austria, France, Germany, Italy, Czech Republic, Romania, Slovakia, Slovenia, Switzerland, Hungary).
Retail sales operations are conducted under the Eni and Agip brands. The re-branding of Eni's service stations in Italy and in the rest of Europe to Eni brand is underway.

Eni operates in engineering, construction and drilling both offshore and onshore for the oil&gas industry through the subsidiary Saipem.

In April 2012, Eni in collaboration with ZEiTECS announced the world's first offshore rigless/wireline retrievable ESP system for Eni Congo.

Eni's principal subsidiaries include:

The Central Energy Italian Gas Holding scandal in 2005 involved Eni and Gazprom

In 2009, the European Commission filed formal antitrust charges against Eni. The commission believes that Eni has conspired to keep competitors from using its gas pipelines.

In 2009 again, according to the WikiLeaks cables, US ambassador Lanier told Washington that bribery allegations were made in Uganda by Eni which at the time was in competition for oil assets in the country against Tullow Oil. The bribes were taken by the newly appointed Ugandan prime minister, Amama Mbabazi.

After corruption charges against the subsidiary Saipem, Eni's CFO Alessandro Bernini had to resign and the new CFO Massimo Mondazzi took over in December 2012.

Eni has been included into the Dow Jones Sustainability World Index since 2007.

In 2012 Eni is confirmed on the FTSE4Good Index for the sixth consecutive year.

In 2012 Eni is also included in the Carbon Performance Leadership Index and is the only FTSE MIB company to gain the triple E for Standard Ethics.

During 2012, Eni decreased CO₂ emission that resulted from flaring by 10% as compared to 2011.

In 2013 Eni has been confirmed in the Dow Jones Sustainability Indices and, in the half-yearly review in March 2014, also in the FTSE4 good sustainability index.

In 2013 Eni continued its commitment to integrated reporting, preparing the Annual Report 2013 in accordance with the principles and contents of the integrated reporting (IR) framework issued by the International Integrated Reporting Council (IIRC).

Among the UN Sustainable Development Solution Network (SDSN), in 2013 Eni led the Energy For All in Sub-Saharan Africa initiative through international collaborations aimed at devising solutions to fight against energy poverty, in particular in Sub-Saharan Africa.

In 2013 Eni's commitment continued in ensuring access of local communities to energy, particularly in Sub-Saharan Africa.

In the first half of 2014 Eni achieved the start-up of the Porto Torres green chemistry plant and the Venice biorefinery.

The Board of Directors is comprised as follows as of February 2017:
Emma Marcegaglia, former president of General Confederation of Italian Industry (Chairwoman of the Board)
Claudio Descalzi, current CEO of Eni
Andrea Gemma, law professor at Roma Tre University
Pietro Guindani, former CEO and CFO of Vodafone Italy
Karina Litvack, former Director of Ethics and Corporate Governance for F&C Asset Management
Alessandro Lorenzi, former Vice President of Planning and Control at Ferrero SpA, former CFO of Coin Group, former CCO for Lavazza
Diva Moriani, current CEO of KME Vorstand
Fabrizio Pagani, current Secretary of Technology for Ministry of Economy and Finance (Italy), former OECD senior advisor and head of G8/G20 office
Alessandro Profumo, former CEO of Unicredit