The clause expires in mid-July, creating a tight window for Brighton to act before any negotiated fee with Köln would have to be agreed separately.
Kaminski, 24, was born in Ruda Śląska in southern Poland and came through the academy at Lech Poznań, where he made his Ekstraklasa debut in 2019 before going on to play a key role in the club's championship-winning 2021-22 season — a campaign that earned him the league's Young Player of the Year award.
VfL Wolfsburg signed him that summer and he spent three seasons there before Cologne took him on loan last year, subsequently activating a €5.5m purchase option — a buy that looks increasingly astute given the transfer activity now surrounding him.
Last season at Köln he scored seven goals and provided three assists in the Bundesliga, playing across multiple positions in the attack.
He has 31 caps for Poland and has made no secret of where he wants to go next.
"My dream was always to play in the Bundesliga, but after 104 games and four seasons that is done," Kaminski said earlier this month.
"My next dream is the Premier League. It is the best league in the world. I would love to prove myself there."
Brighton are the most realistic destination, though the club are aware that other teams could comfortably match the release fee, and the mid-July expiry date means there is little room to delay.
A move to Brighton would represent a significant step up for Kaminski and the fulfilment of an ambition he has carried since his breakthrough years in Poland. Brighton's interest signals they see him as a direct wide option capable of contributing in a team that routinely challenges for European qualification.
For Köln, losing Kaminski so soon after permanently signing him would be a blow to their attacking options, even if the financial return — a profit of around €14.5m on a player bought for €5.5m just months ago — softens it considerably.