Gottfried Leibniz (1646 - 1716)

Turn human language into formal grammar,
Then we can settle disagreements with a pencil.

Or a calculating machine.


"If controversies were to arise there would be no more need of disputation...
For it would suffice to take their pencils in their hands, and say to each other,

Let's Calculate"

Everyone knows the rules, no need to sue

Direct Payment

More logic

A pays B

If X happens A pays B

If not money goes back to A

A and B pay

If X happens A gets paid

if Y happens B gets paid

Huge range of applications

Financial derivatives


Contracts based on performance


Watch this space


Transactions are connected to reality

But bitcoin nodes don't know what reality is

Confused Nodes

The internet used to have the same problem with identity

Who is Amazon?

We solved it with the Certificate Authority

Who is Amazon? Oh, that's Amazon

Reality Keys: A Certificate Authority for Facts

Reality Keys

Data Sources

Exchange rates: ECB, Coindesk


Runkeeper: Exercise tracking

Freebase: Everything in the known universe

Adding more all the time


Publish keys identifying the fact (one true, one false)

Parties use the keys to lock money in a transaction

Publish a private key certifying the outcome

Winning party unlocks funds

Optional human verification (for a fee) protects against bad data


Free, anonymous API

We don't need to know anything about the transaction

Certificates can by cryptographically blinded so we can't see them

See our developers' section for code samples

Build what you like, disrupt insurance, derivatives, job contracts...

Supported platforms

We just provide keys for facts, we don't care what you do with them

You may just want to encrypt

About to get a lot easier on Bitcoin (0.10)

All Bitcoin 2.0 platforms need certified data sources

Considering support for Counterparty, Ethereum etc

(Technical) How the keys work on bitcoin [1]

1 BTC to be > 500 Euros on June 1

(Technical) How the keys work on bitcoin [2]

1 BTC was > 500 Euros on June 1

(Technical) The network looks after the money

Alice and Bob's Contract

(Technical) The result is known, the winner unlocks funds

Settling Alice and Bob's Contract

(Technical) m of n

Who is Amazon? Oh, that's Amazon