The Sans Girisim venture of Demiroren and U.S. firm Scientific Games made an offer to take 0.2 percent of revenues under the revenue-sharing scheme, revising down their previous bid of 2.1 percent, NTV and other Turkish media said.
The other bidder in the tender, the Inteltek venture of Intralot and Turkish mobile phone operator Turkcell offered to take a 0.5 percent commission, after having offered 1.4 percent in the first round of bidding.
Turkcell's shares were down 0.27 percent at 0821 GMT.
Demiroren Holding and Turkcell were not immediately available to comment on Wednesday morning.
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Demiroren Holding, which also owns major media outlets in Turkey, is owned by Yildirim Demiroren, the current chairman of the Turkish Football Federation (TFF).
All other betting and gambling platforms are banned in Turkey.
(Reporting by Tuvan Gumrukcu; Editing by Ece Toksabay; Editing by Kirsten Donovan)
