Ltd. which consists of former Indian cricket captain Sourav Ganguly, alongside businessmen Harshavardhan Neotia, Sanjiv Goenka and Utsav Parekh.

On 16 January 2020, it was announced that the RPSG Group along with former cricketer Sourav Ganguly and businessmen Utsav Parekh, had bought an 80% stake in Mohun Bagan Football Club (India) Pvt.

[5] On 13 April 2014, it was announced that Sourav Ganguly, Harshavardhan Neotia, Sanjiv Goenka, Utsav Parekh, and Spanish La Liga side Atlético Madrid had won the bid for the Kolkata franchise.

[8] The team then went on to sign two more Spaniards: their first head coach, Antonio López Habas, and marquee player, former UEFA Champions League winner Luis García, on 8 July 2014.

The first Indian signing by the club took place in round one of the 2014 ISL Inaugural Domestic Draft in which Atlético de Kolkata selected Cavin Lobo, midfielder for the city's I-League team East Bengal FC, with their pick.

[10] In the International Draft, four of Atlético de Kolkata's allotted seven picks were Spaniards, including defender Josemi, a UEFA Champions League winner with Liverpool in 2005.

[13] By finishing third in the league, the club qualified for the end-of-season play-offs, where they advanced via a penalty shootout past FC Goa in the semi-finals after a goalless draw.

[14] At the final against the Kerala Blasters at the DY Patil Stadium in Mumbai, Atlético won 1–0 with an added-time goal by Mohammed Rafique.

[16] On 5 June 2015, the team acquired Canadian international forward Iain Hume, whose five goals had helped Kerala to the final of the previous season.

[17] In the second season's domestic draft, Atlético de Kolkata had the first pick, choosing Pune FC goalkeeper Amrinder Singh for a fee of 450,000; their most expensive purchase was that of defender Augustin Fernandes for 2.6 million.

[20] Postiga scored twice in Atlético's first game of the season, a 3–2 win at Chennaiyin FC, but was substituted later in the match due to injury, and missed the rest of the campaign.

[21] Pelé, regarded as one of the greatest footballers of all time, watched the 2–1 win over Kerala at the Salt Lake Stadium on 13 October, Atlético's first home game of the season.

[32] In the final, away to Kerala on 18 December, Kolkata fell behind to a goal by their former player Mohammed Rafi, and equalised before half-time with a header by defender Henrique Sereno.

[35] On 24 January 2018, Sheringham was sacked by ATK after winning only three of his ten games in charge and appointed Ashley Westwood as their interim coach.

[36] For the first time in four years the club could not make it to the playoffs, but avoided last place by registering a 1–0 win over NorthEast United FC in the final game, Robbie Keane netting the deciding goal.

On 7 July, the team's jersey and logo were unveiled by West Bengal Chief Minister Mamata Banerjee at the Nabanna building, temporary headquarters of the state's secretariat.

The fourth season saw a formidable decline in the average attendance in the home matches of Kolkata due to the low capacity of Rabindra sarobar stadium.

The consortium is made up of former India cricket captain Sourav Ganguly, businessmen Harshavardhan Neotia, Sanjiv Goenka, and Utsav Parekh.

[1] The club's initial sponsors were Indian telecommunications corporation Aircel, while its partners were Kolkata-based underwear brand Lux Cozi and insurance firm Apollo Munich.