Detecting data breaches

1. A method for detecting data breaches, the method comprising:

receiving, by a computer system and from each of a plurality of data owners, a first cryptographically secure representation of data to be monitored for data breaches, each first cryptographically secure representation including a cryptographically secure data structure that represents a plurality of first data records maintained by the data owner;

receiving, from a user and for each of a plurality of second data records, one or more second cryptographically secure representations of the second data records;

determining, by the computer system, a number of the second cryptographically secure representations that match a corresponding portion of the first cryptographically secure representation received from a data owner of the plurality of data owners;

determining, by the computer system, that the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner meets or exceeds a predetermined threshold; and

determining, by the computer system, that a data breach occurred for the data owner based at least in part on determining that the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner meets or exceeds the predetermined threshold.

2. The method of claim 1 , further comprising providing notification to the data owner notifying the data owner of the breach in response to determining that the breach occurred.

3. The method of claim 1 , wherein each first cryptographically secure representation comprises a first probabilistic representation and each second cryptographically secure representation comprises a second probabilistic representation.

4. The method of claim 3 , wherein each first probabilistic representation comprises a first Bloom filter.

5. The method of claim 4 , wherein each second probabilistic representation comprises one or more bit numbers that each identifies a respective bit of a second Bloom filter that has been set based on the second data record represented by the second probabilistic representation.

6. A method for detecting data breaches, the method comprising:

receiving, by a computer system and from each of a plurality of data owners, a first cryptographically secure representation of data to be monitored for data breaches, each first cryptographically secure representation including a cryptographically secure data structure that represents a plurality of first data records maintained by the data owner;

receiving, from a user and for each of a plurality of second data records, one or more second cryptographically secure representations of the second data records, wherein:

each first cryptographically secure representation comprises a first probabilistic representation and each second cryptographically secure representation comprises a second probabilistic representation;

each first probabilistic representation comprises a first Bloom filter; and

each second probabilistic representation comprises one or more bit numbers that each identifies a respective bit of a second Bloom filter that has been set based on the second data record represented by the second probabilistic representation;

determining, by the computer system, a number of the second cryptographically secure representations that match a corresponding portion of the first cryptographically secure representation received from a data owner of the plurality of data owners, wherein determining a number of the second cryptographically secure representations that match a corresponding portion of the cryptographically secure representation received from a data owner of the plurality of data owners comprises:

for each second probabilistic representation received from the user:

determining, for each data element of the second probabilistic representation, whether the data element matches a corresponding data element of the first Bloom filter; and

incrementing a count of a number of matching probabilistic representations when each data element of the second probabilistic representation matches the corresponding data element of the first Bloom filter; and

determining, by the computer system, that a data breach occurred for the data owner based on the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner.

7. A method for detecting data breaches, the method comprising:

receiving, by a computer system and from each of a plurality of data owners, a first cryptographically secure representation of data to be monitored for data breaches, each first cryptographically secure representation including a cryptographically secure data structure that represents a plurality of first data records maintained by the data owner;

receiving, from a user and for each of a plurality of second data records, one or more second cryptographically secure representations of the second data records;

determining, by the computer system, a number of the second cryptographically secure representations that match a corresponding portion of the first cryptographically secure representation received from a data owner of the plurality of data owners; and

determining, by the computer system, that a data breach occurred for the data owner based on the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner, wherein determining that a data breach occurred for the data owner based on the number of the second cryptographically secure representations that match the corresponding portion of the cryptographically secure representation received from the data owner comprises determining that a percentage of the second cryptographically secure representations received from the user match the corresponding portion of the cryptographically secure representation received from the data owner.

8. The method of claim 1 , wherein each data record of each of the first cryptographically secure representations includes a tuple having multiple related data items.

9. The method of claim 1 , wherein the first cryptographically secure representation received from a given data owner represents, for each entity of a plurality of entities, multiple tuples of a data record for the entity, each tuple comprising a different set of data related to the entity and included in the data record.

10. The method of claim 1 , further comprising providing compensation to the user in response to determining that the breach occurred for the data owner using the second cryptographically secure representations received from the user.

11. A method for detecting data breaches, the method comprising:

receiving, by a computer system and from each of a plurality of data owners, a first cryptographically secure representation of data to be monitored for data breaches, each first cryptographically secure representation including a cryptographically secure data structure that represents a plurality of first data records maintained by the data owner;

receiving, from a user and for each of a plurality of second data records, one or more second cryptographically secure representations of the second data records;

receiving, from the user, data specifying a requested compensation amount for detection of a breach using the second cryptographically secure representations received from the user; and

determining, for each data owner of the plurality of data owners and based on the requested compensation amount, whether to compare the second cryptographically secure representations to the first cryptographically secure representation received from the data owner;

in response to determining to compare the second cryptographically secure representations to the first cryptographically secure representation received from a particular data owner of the plurality of data owners:

determining, by the computer system, a number of the second cryptographically secure representations that match a corresponding portion of the first cryptographically secure representation received from the particular data owner; and

determining, by the computer system, that a data breach occurred for the data owner based on the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner.

12. A system comprising:

a data processing apparatus; and

a non-transitory computer storage medium encoded with a computer program, the program comprising data processing apparatus instructions that when executed by the data processing apparatus cause the data processing apparatus to perform operations comprising:

receiving, from each of a plurality of data owners, a first cryptographically secure representation of data to be monitored for data breaches, each first cryptographically secure representation including a cryptographically secure data structure that represents a plurality of first data records maintained by the data owner;

receiving, from a user and for each of a plurality of second data records, one or more second cryptographically secure representations of the second data records;

determining a number of the second cryptographically secure representations that match a corresponding portion of the first cryptographically secure representation received from a data owner of the plurality of data owners;

determining that the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner meets or exceeds a predetermined threshold; and

determining that a data breach occurred for the data owner based at least in part on determining that the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner meets or exceeds the predetermined threshold.

13. The system of claim 12 , wherein the operations comprise providing notification to the data owner notifying the data owner of the breach in response to determining that the breach occurred.

14. The system of claim 12 , wherein each first cryptographically secure representation comprises a first probabilistic representation and each second cryptographically secure representation comprises a second probabilistic representation.

15. The system of claim 14 , wherein each first probabilistic representation comprises a first Bloom filter.

16. The system of claim 15 , wherein each second probabilistic representation comprises one or more bit numbers that each identifies a respective bit of a second Bloom filter that has been set based on the second data record represented by the second probabilistic representation.

17. A method for detecting data breaches, the method comprising:

receiving, by a computer system and from a plurality of data owners, first cryptographically secure representations of data to be monitored for data breaches, each first cryptographically secure representation including a cryptographically secure data structure that represents a plurality of first data records maintained by the data owner;

receiving, by the computer system and from a user, a plurality of second data records;

generating, by the computer system and for each second data record received from the user, one or more second cryptographically secure representations of the second data record;

determining, by the computer system, a number of the second cryptographically secure representations that match a corresponding portion of the first cryptographically secure representation received from a data owner of the plurality of data owners;

determining, by the computer system, that the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner meets or exceeds a predetermined threshold; and

determining, by the computer system, that a data breach occurred for the data owner based at least in part on determining that the number of the second cryptographically secure representations that match the corresponding portion of the first cryptographically secure representation received from the data owner meets or exceeds the predetermined threshold.

18. The method of claim 17 , further comprising providing notification to the data owner notifying the data owner of the breach in response to determining that the breach occurred.

19. The method of claim 17 , wherein each first cryptographically secure representation comprises a first probabilistic representation and each second cryptographically secure representation comprises a second probabilistic representation.