Abstract: An auction verification subsystem provides verification, without revealing actual bid values, that bid values remained sealed prior to a closing time for the auction and that an announced winning bidder for the auction provided a highest bid. The verification subsystem receives encrypted bids from bidders and generates commitment data based on the bids and provides the commitment data to each of the bidders. In response to receiving the commitment data, the bidders provide decryption keys for the encrypted bids. In turn, the bids are decrypted and an auction is performed using the decrypted bids. The results of the auction can be verified based on bid representations that do not reveal the actual values of bids, thereby maintaining the secrecy of bids. Providing access to an exchange between bidders and the verification subsystem facilitates verification that the auction is performed as a sealed bid auction.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for facilitating aggregated product requests. In one aspect, a method includes receiving product request data from a plurality of users and determining that an offer request condition has occurred, where the offer request condition specifies a condition under which offers are requested from advertisers. In response to occurrence of the offer request condition, offer request data are provided to advertisers. The offer request data specify a quantity of users from which product request data were received. Offer data are received from advertisers. The offer data specify an offer associated with the particular product and an amount that an advertiser will pay for distribution of the offer. An offer is selected to be provided to the users and presentation data that cause presentation of the selected offer are provided.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for facilitating aggregated market transactions. In one aspect, a method includes receiving inventory data from sellers, where the inventory data specifies an ask price for a particular product and a discount function associated with the product. User input is received from users, where the user input requests information about a particular product. In response to the user input, data are provided that cause presentation of a product request user interface. Bids for the particular product are received from multiple users, and a final price is selected using ask prices, discount function, and bids. In turn, the particular product is allocated to a set of users that specified a bid that meets the final price.

Abstract: An auction verification subsystem provides verification, without revealing actual bid values, that bid values remained sealed prior to a closing time for the auction and that an announced winning bidder for the auction provided a highest bid. The verification subsystem receives encrypted bids from bidders and generates commitment data based on the bids and provides the commitment data to each of the bidders. In response to receiving the commitment data, the bidders provide decryption keys for the encrypted bids. In turn, the bids are decrypted and an auction is performed using the decrypted bids. The results of the auction can be verified based on bid representations that do not reveal the actual values of bids, thereby maintaining the secrecy of bids. Providing access to an exchange between bidders and the verification subsystem facilitates verification that the auction is performed as a sealed bid auction.

Abstract: An auction verification subsystem provides verification, without revealing actual bid values, that bid values remained sealed prior to a closing time for the auction and that an announced winning bidder for the auction provided a highest bid. The verification subsystem receives encrypted bids from bidders and generates commitment data based on the bids and provides the commitment data to each of the bidders. In response to receiving the commitment data, the bidders provide decryption keys for the encrypted bids. In turn, the bids are decrypted and an auction is performed using the decrypted bids. The results of the auction can be verified based on bid representations that do not reveal the actual values of bids, thereby maintaining the secrecy of bids. Providing access to an exchange between bidders and the verification subsystem facilitates verification that the auction is performed as a sealed bid auction.

Abstract: Systems and methods are disclosed for privacy-preserving flexible user-selected anonymous and pseudonymous access at a relying party (RP), mediated by an identity provider (IdP). Anonymous access is unlinkable to any previous or future accesses of the user at the RP. Pseudonymous access allows the user to associate the access to a pseudonym previously registered at the RP. A pseudonym system is disclosed. The pseudonym system allows a large number of different and unlinkable pseudonyms to be generated using only a small number of secrets held by the user. The pseudonym system can generate tokens capable of including rich semantics in both a fixed format and a free format. The tokens can be used in obtaining from the IdP, confirmation of access privilege and/or of selective partial disclosure of user characteristics required for access at the RPs. The pseudonym system and associated protocols also support user-enabled linkability between pseudonyms.