sealed bid

Translations
запечатанная ставка
Someone submitted a sealed bid for the auction.
Кто-то подал запечатанную ставку на аукцион.
Definitions
A sealed bid is a type of bidding process in which all bidders submit their offers confidentially and simultaneously, without knowledge of the other bids. The bids are then opened at a specified time, and the highest or most favorable bid is typically accepted.