Stablecoin Payments Security: How MPC Protects Enterprise Payment Infrastructure
How MPC protects signing, approvals, and key operations in enterprise payment systems.
Written by
Berwin D
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Jun 22, 2026
Stablecoin transaction volume reached $28 trillion in adjusted economic activity in 2025, growing at a 133% compound annual growth rate since 2023. The stablecoin payment infrastructure market was valued at $7.6 billion in 2025 and is projected to reach $89.4 billion by 2034 at a 32.1% CAGR. Visa, Mastercard, Stripe, PayPal, and Western Union have all integrated or announced plans to adopt stablecoin rails.
The infrastructure is maturing. The security question is sharpening. Every stablecoin payment requires a cryptographic signature. The private key that produces that signature is the single most critical piece of infrastructure in the payment flow. How that key is stored, managed, and used determines whether the platform can scale to institutional-grade volumes without becoming a high-value target.
The Signing Key Problem in Stablecoin Payments
Every stablecoin transaction is a blockchain transaction. It requires a private key to sign. The platform that processes the payment must either hold the key, delegate the key, or distribute the key.
Holding the key on a single server creates a concentrated attack target. The $1.5 billion Bybit breach in early 2025 demonstrated what happens when signing infrastructure is compromised at a single point. A single key on a single server is the highest-risk architecture for any payment platform processing meaningful volume.
Delegating the key to a third-party custodian shifts the risk but does not eliminate it. The platform depends on the custodian's security, uptime, and regulatory status. If the custodian is compromised or goes offline, the platform's payment flow stops.
Distributing the key using MPC eliminates the single point of failure. The key is split into shares distributed across multiple servers, devices, or environments. A threshold number of shares coordinate to produce a valid signature without the full key ever existing in any single location.
For stablecoin payment platforms processing high volumes across multiple chains and jurisdictions, MPC-based signing is the architecture that scales without concentrating risk.
How MPC Secures Stablecoin Payment Infrastructure
MPC threshold signatures protect the signing operation at the core of every stablecoin payment. The payment platform distributes key shares across its infrastructure. When a payment needs to be authorized, the required threshold of shares coordinate to produce a signature. The signature is standard ECDSA or EdDSA. The blockchain cannot distinguish it from a single-key signature.
This provides three critical properties for payment platforms.
No single point of compromise. An attacker who compromises one server gains one key share, which cannot produce a valid signature on its own. The attacker would need to compromise the threshold number of servers simultaneously, across different network segments, to authorize a fraudulent payment.
Chain agnosticism. MPC signatures work on any blockchain that accepts standard signatures. A stablecoin platform supporting USDC on Ethereum, USDT on Tron, and PYUSD on Solana can use the same MPC infrastructure across all chains, without requiring chain-specific multisig contracts.
Operational continuity. Key shares can be rotated, devices can be replaced, and threshold configurations can be updated without changing the wallet address or migrating funds. This is critical for payment platforms that cannot afford downtime during infrastructure changes.
Silent Pay: MPC-Secured Stablecoin Payments
Silent Pay is Silence Laboratories' stablecoin payment product. It provides enterprise-grade MPC signing infrastructure packaged with the integrations a payment platform needs to go live.
Silent Pay is built on the same MPC infrastructure that secures BitGo's institutional custody ($90+ billion in assets under custody) and Okto's consumer wallets (17 million wallets). The underlying Silent Shard SDK implements the DKLs23 protocol, generating threshold signatures in under 20ms.
Single integration. Silent Pay comes packaged with on/off ramp capabilities, stablecoin networks, ACH, SEPA, SWIFT, and blockchain integrations. A platform integrates once and accesses the full payment stack.
Pre-built components. APIs and pre-built components provide a ready, out-of-the-box experience for payment platforms that need to go to market quickly.
Compliance. Funds move through licensed partners in each jurisdiction, ensuring compliance with local regulations.
Rewards on idle funds. Earn yield through tokenized money market funds on idle cash through integrated partners.
Target Verticals
Silent Pay targets four verticals, each with distinct security and compliance requirements.
Banks and neobanks adding stablecoin payment capabilities to their existing product suite. The MPC signing infrastructure meets the key management requirements that banking regulators expect, including distributed key control and audit trail generation.
Payment service providers (PSPs) integrating stablecoin settlement into existing payment rails. The single-integration architecture means PSPs do not need to build separate infrastructure for each stablecoin network.
Remittance providers offering instant cross-border payouts. Stablecoin remittances and P2P payments hit a $19 billion annualized run rate as of August 2025. MPC signing enables instant settlement without the pre-funding requirements of traditional correspondent banking.
Payroll platforms using stablecoins for cross-border salary payments. 226 new businesses integrated stablecoins for payroll in 2025, with companies like Deel and Flywire adopting stablecoin rails for cross-border payouts.
Comparison: Stablecoin Payment Infrastructure Approaches
Dimension | Single Key | Multisig | MPC (Silent Pay) |
|---|---|---|---|
Key exposure | Full key on one server | Full keys per signer | No complete key exists anywhere |
Chain support | All | Chain-dependent | All ECDSA/EdDSA chains |
Signing speed | Instant | Requires multiple signers | Under 20ms (DKLs23) |
Key rotation | Requires new wallet | Requires new wallet/contract | Rotate shares, same address |
Regulatory fit | Unacceptable for institutions | Acceptable | Preferred by regulated entities |
Single point of failure | Yes | Reduced | Eliminated |
Regulatory Landscape for Stablecoin Payments
GENIUS Act (US). The GENIUS Act, signed into law in mid-2025, created the first federal regulatory framework for payment stablecoins in the US. It defines stablecoins issued by permitted issuers as payment instruments. Banks can now act as stablecoin custodians and issue their own stablecoins. Payment platforms must meet reserve, disclosure, and governance requirements.
MiCA (EU). The Markets in Crypto-Assets Regulation requires stablecoin issuers and service providers in the EU to obtain authorization. MiCA catalyzed a 245% increase in licensed stablecoin service providers within the EU between January 2024 and March 2026.
MAS Payment Services Act (Singapore). Digital payment token service providers must be licensed by the Monetary Authority of Singapore. MPC-based key management aligns with MAS TRM requirements for distributed key control and technology risk management. Silence Laboratories is headquartered in Singapore and builds its infrastructure for MAS-regulated environments.
India. India is the largest remittance-receiving country globally at over $125 billion annually. The Asia-Pacific region is projected to register the highest CAGR of 25.1% in stablecoin payment infrastructure through 2034, driven by smartphone penetration and digital banking expansion.
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FAQ
Why do stablecoin payment platforms need MPC? Every stablecoin payment requires a cryptographic signature. The private key that produces that signature must be protected against compromise. MPC distributes the key into shares so that no single server, device, or person ever holds the complete key. This eliminates the single-point-of-failure risk that has led to billion-dollar breaches.
What is Silent Pay? Silent Pay is Silence Laboratories' stablecoin payment product. It packages MPC-based signing infrastructure with on/off ramp, ACH, SEPA, SWIFT, and blockchain integrations so payment platforms can go live with a single integration.
Does MPC signing work across all stablecoin networks? Yes. MPC threshold signatures produce standard ECDSA or EdDSA signatures that work on any blockchain. A platform using Silent Pay can support USDC, USDT, PYUSD, and other stablecoins across Ethereum, Solana, Tron, Base, and other networks from the same MPC infrastructure.
What regulations apply to stablecoin payment platforms? The GENIUS Act (US) defines stablecoins as payment instruments. MiCA (EU) requires authorization for stablecoin service providers. MAS PSA (Singapore) requires licensing for digital payment token services. Each jurisdiction has specific requirements for reserve management, disclosure, key management, and consumer protection.
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