EMI was listed on the London Stock Exchange, and was also once a constituent of the FTSE 100 Index, but faced financial problems and US$4 billion in debt, leading to its acquisition by Citigroup in February 2011.

Other members of the Sony consortium include the estate of Michael Jackson, the Blackstone Group, and the Abu Dhabi–owned Mubadala Development Company.

During and after World War II, the EMI Laboratories in Hayes, Hillingdon developed radar equipment (including the receiver section of the British Army's GL-II anti-aircraft fire-control radar), microwave devices such as the reflex klystron oscillator (having played a crucial role in the development of early production types following on from the British Admiralty Signal School's pioneering NR89, the so-called "Sutton tube"), electro-optic devices such as infra-red image converters, and eventually guided missiles employing analogue computers.

The EMI Electronic Business Machine, a valve and magnetic drum memory computer, was built in the 1950s to process the British Motor Corporation payroll.

[17] In the early 1970s, with financial support by the UK Department of Health and Social Security as well as EMI research investment,[18] Hounsfield developed the first CT scanner, a device which revolutionised medical imaging.

It manufactured integrated circuits, electrolytic capacitors and, for a short period in the mid-1970s, hand-held calculators under the Gemini name.

[21] Early in its life, the Gramophone Company established its subsidiary operations and branch offices in a number of many other countries inside and outside of the British Commonwealth, including Europe, the Middle East and Africa as well as in Canada, Russia, India, China, Japan, Australia and New Zealand.

Victor owned 50% of the British affiliated Gramophone Company, giving RCA chairman David Sarnoff a seat on the EMI board.

From 1960 to 1995, their "EMI House" corporate headquarters was located at 20 Manchester Square London, England, the stairwell from which was featured on the cover of the Beatles' Please Please Me album.

In addition, an unused shot from the Please Please Me photo session, featuring the boys in short hair and cleancut attire, was used for the cover of the Beatles' first double-disc greatest-hits compilation entitled 1962–1966 (also known as "The Red Album").

From the late 1950s to the early 1970s, the company enjoyed huge success in the popular music field under the management of Sir Joseph Lockwood.

The strong combination of EMI and its subsidiary labels (including Parlophone, HMV, Columbia and Capitol Records) along with a roster of stellar groups such as the Hollies, the Shadows, the Beach Boys and the Beatles along with hit solo performers such as Frank Sinatra, Cliff Richard, and Nat 'King' Cole, made EMI the best-known and most successful recording company in the world at that time.

For the emerging progressive rock genre including Pink Floyd, who had debuted on Columbia, EMI established a new subsidiary label, Harvest Records, two years later.

[27] Due to the increasing divergence of business models, Thorn EMI shareholders voted in favour of demerger proposals on 16 August 1996.

[36] In May 2006, EMI attempted to buy Warner Music Group, which would have reduced the world's four largest record companies (Big Four) to three; however, the bid was rejected.

[38] After a decline in the British market share from 16% to 9%, and the announcement that it had sustained a loss of £260 million in 2006/2007,[39][40] in August 2007 EMI was acquired by Terra Firma Capital Partners[39] for £4.2 billion.

[44] The Terra Firma takeover was also reported to have been the catalyst behind a lawsuit filed by Pink Floyd over unpaid royalties.

[46] Around the same time, Guy Hands, CEO of Terra Firma Capital Partners, came to EMI with restructuring plans to cut between 1,500 and 2,000 jobs[40] and to reduce costs by £200 million a year.

[47] The suit was later settled following a defence based on a contract case involving actress Olivia de Havilland decades before.

In 2008, EMI withdrew from the South-East Asian market entirely, forcing its large roster of acts to search out contracts with other unaffiliated labels.

[53] In February 2010, EMI Group reported pre-tax losses of £1.75 billion for the year ended March 2009, including write-downs on the value of its music catalogue.

[62] In March 2012, the European Union opened an investigation into Universal's purchase of EMI's recorded music division[63] and had asked rivals and consumer groups whether the deal will result in higher prices and shut out competitors.

[71] Universal retained EMI's former European labels in Ireland, Italy, the Netherlands, Germany, Switzerland, Austria, Hungary, and Finland.

[77] On 30 June 2014, Universal Music Group re-established EMI's Taiwanese division, with A-Mei, Rainie Yang and Show Lo signing first to the label.

The European Chrysalis catalogue, including Harry's four albums, plus the rights to ten artists not originally signed to the label are owned and distributed by Blue Raincoat.

[93] Following the merger with Thorn, part of EMI's leisure interests were sold to Trust House Forte in November 1980 for £16 million.

[92] As well as Angus Steakhouse, their restaurants also included Wimpy Bars, Picnic Basket and Tennessee Pancake Houses.

[92] Following the merger with Thorn, seven hotels and 12 Angus Steakhouse restaurants were sold in July 1980 for £23 million to Scottish & Newcastle Breweries.

[citation needed] EMI administered the publishing rights of over 1.3 million songs, headlined by Queen, Carole King, The Police, the Motown catalog, Kanye West, Alicia Keys, Drake, Sia, P!nk, Pharrell Williams, and Calvin Harris.

[100] On Internet Freedom Day in January 2013, EMI evoked controversy after the removal of Martin Luther King Jr's "I Have a Dream" speech from Vimeo due to a copyright violation.