UPDATE: Oct. 14, 2019: Booking Holdings, the online travel company that runs Kayak.com and Priceline.com pulled out of the Libra Association before the remaining 21 companies backing the project signed its charter, Bloomberg reported Monday.
EBay, Stripe, Mastercard and Visa have dropped out of the Libra Association, Facebook's cryptocurrency project, the companies announced Friday. The collective decision to exit the project follows payment company PayPal's departure last week.
The series of exits come after Sens. Brian Schatz, D-HI, and Sherrod Brown, D-OH, on Tuesday, sent letters to the CEOs of Visa, Mastercard and Stripe, urging them to reconsider their association with the project.
The exits are a big blow and come as Facebook CEO Mark Zuckerberg is scheduled to testify in front of the House Financial Services Committee on Oct. 23 regarding his company's impact on financial services and housing.
Of the original 28 backers, six now have abandoned the Libra project. PayPal withdrew last week, and Mercado Pago has also left. Representatives of the 22 companies who continue to back the project are expected to sign the Libra Association charter Monday at a meeting in Geneva.
Members signed nonbinding agreements before the currency was unveiled in June. However, they haven't yet been required to submit the agreed $10 million-apiece investment in the project.
"We highly respect the vision of the Libra Association; however, eBay has made the decision to not move forward as a founding member. At this time, we are focused on rolling out eBay's managed payments experience for our customers," a company spokesperson told the Financial Times.
In a statement to the Financial Times, Stripe said it "is supportive of projects that aim to make online commerce more accessible for people around the world. Libra has this potential."
The San Francisco-based payment company said it would follow the project's progress closely and remain open to working with the Libra Association at a later stage.
A Visa spokesperson told CNBC the company "will continue to evaluate and our ultimate decision will be determined by a number of factors, including the Association's ability to fully satisfy all requisite regulatory expectations. Visa's continued interest in Libra stems from our belief that well-regulated blockchain-based networks could extend the value of secure digital payments to a greater number of people and places, particularly in emerging and developing markets."
Libra said it plans to move forward with its Monday meeting as scheduled.
"We look forward to the inaugural Libra Association council meeting in just three days and announcing the initial members of the Libra Association," a Libra spokesperson told the Financial Times.
Government officials in the U.S. and Europe have scrutinized Libra's development from the beginning. In their letters to payment companies this week, Schatz and Brown said they were unsure Facebook was taking seriously the risks presented by Libra with regard to money laundering and terrorism financing.
The European Union's antitrust chief, Margrethe Vestager, said she's wary the currency could create a new, separate economy. Bruno Le Maire, France's finance minister, urged the continent last month to block the currency and create a public alternative.