It is the most exclusive club in European rugby, but next week three Leinster aces could swell the ranks of those who have collected four winners' medals if the Blues beat Racing 92 in Bilbao.
A fourth title would put the Irish province on par with Toulouse as the most successful club in European history, and former Toulouse duo Frederic Michalak and Cedric Heymans are the only players to have won it four times.
Indeed, nobody has yet won all four with the same club, meaning Cian Healy and Johnny Sexton, Isa Nacewa and Devin Toner could make history.
Although seven Leinster players have the hat-trick of medals from their glorious period between 2009 and 2012, only that trio are still playing.
If Leo Cullen sticks largely with the same team that won the semi-final against Scarlets, and Leinster win, then Sexton, Nacewa and Healy will become the first players to have started four winning finals.
Healy's return to full form has been a big component in his side's success this year, while the return of Sexton and Nacewa - who both spent two years away since the 2012 success - has been pivotal in the re-emergence of the province as a force.
Nacewa started the 2009 and 2011 finals at full-back, before reverting to the wing in 2012, while Sexton was starting out-half and Healy the loosehead in all three.
Toner was an unused replacement in 2009, but was introduced in the second and third successes. Of the 22 players named for Leinster's first final success nine years ago, 16 have retired and three are part of the current management.
One of those is former skipper Cullen, who would make his own piece of history if he guides the team to a fourth star. Already the most decorated captain in European rugby history, the former second-row would become the first person to coach and play on winning teams if they succeed.
Although he was captain in 1999 and lifted the trophy with David Humphreys, injury prevented Saracens boss Mark McCall from playing a major role in Ulster's 1999 success.
If Racing win, their co-coach Laurent Travers would beat Cullen to that prize as he was hooker on the Brive side 21 years ago.
Success for Leinster would bring the total number of Irish European wins to seven, one behind the French and English.