#3 ATK - 2016
2016 was a peculiar year in the ISL, with the previous year's finalists both finishing in the bottom two. Furthermore, the top two teams from the league stages in 2016, Mumbai City FC and Delhi Dynamos, both lost their semifinal matches - to ATK and Kerala Blasters respectively.
The final itself was a spectacle, at the Jawaharlal Nehru Stadium in Kochi, as the Kerala faithful thronged the stadium in large numbers hoping to see their side lift their first ISL crown.
They got off to a great start as well, as local boy Mohammed Rafi headed home from a corner to give the Blasters the lead.
However, they were pegged back soon after, as Henrique Sereno equalised for ATK. The game eventually went into a penalty shootout.
Iain Hume missed the first penalty in the shootout, but Debjit Majumder stepped up in goal for ATK to save a decisive penalty from Cedric Hengbart, after Elhadji Ndoye had also missed for Kerala Blasters.
Jewel Raja Shaikh scored the decisive penalty for ATK to make them two-time champions.
#4 Chennaiyin FC - 2017-18
This was the first year of an expanded ISL, with Bengaluru FC and Jamshedpur FC joining the fold, alongside the eight existing teams.
Bengaluru were dominant in the league stages, amassing 40 points to finish ten points clear of Chennaiyin, who were second.
Both Chennaiyin and Bengaluru made the final, beating FC Goa and FC Pune City in their respective semifinals. The title clash between the two southern rivals took place at the Sree Kanteerava Stadium in Bengaluru.
Sunil Chhetri gave Bengaluru the early lead, and they looked set to push on and claim their maiden ISL crowns, but Chennaiyin roared back to silence the Kanteerava faithful.
Two corners saw Mailson Alves rise highest to head past Gurpreet Singh Sandhu, before Raphael Augusto scored a superb goal on the counter-attack to put Chennaiyin up 3-1.
Miku scored a late goal for Bengaluru to half Chennaiyin's lead, but they held on to win their second ISL crown.
#5 Bengaluru FC - 2018-19
As in 2017-18, Bengaluru FC once again topped the ISL league stages in 2018-19, but this time they only finished ahead of Goa because of their head-to-head record against Sergio Lobera's side.
Once again, the top two sides met in the final, which was played at the Mumbai Football Arena. Goa had fond memories of playing at the Andheri Sports Complex, having beaten Mumbai City FC 5-1 in the first leg of the semifinal there.
Bengaluru went through to the final after overturning a 2-1 deficit from the firs tleg, to beat NorthEast United 4-2 on aggregate.
The final was a cagey affair, with chances at a premium. It seemed to be heading into a penalty shootout until local boy Rahul Bheke stepped up in his hometown for Bengaluru.
Bheke sent an outswinging Dimas Delgado corner looping past Naveen Kumar in the Goa goal in the 117th minute of the final, and there was no coming back from there for Goa.
#6 ATK - 2019-20
Antonio Lopez Habas was re-appointed as head coach of ATK prior to the 2019-20 season, after the franchise endured two particularly disappointing seasons since they won it in 2016.
Chennaiyin FC also made the final, after a spectacular mid-season turnaround following Owen Coyle's arrival to replace John Gregory as the head-coach.
In the final, the more clinical team prevailed, as ATK took the big chances they had, while Chennaiyin didn't.
Arindam Bhattacharya was named the man of the match in the final for a heroic performance between the sticks for ATK.
Javi Hernandez and Edu Garcia put ATK 2-0 up, before Nerijus Valskis halved Chennaiyin's deficit to set up a grand-stand finish.
But Hernandez scored his second of the game in second-half stoppage time to deny Chennaiyin the title, and make ATK the most successful club in the ISL's relatively short history.