Facebook Inc. last week unveiled plans to launch Libra, a payment system it describes as a new “global currency.” It’s based on blockchain, the same technology that powers bitcoin, and is backed by real assets and pegged to stable government securities. Over two dozen corporate partners are on board, including financial companies MasterCard Inc., Visa Inc., PayPal Holdings Inc. and Coinbase. Partners contribute a membership fee of $10 million each. Facebook’s goal is to line up a total of 100 corporate partners and $1 billion in assets.

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