The DS Protocol is Securitize's proprietary securities tokenization infrastructure, developed internally and not submitted to any open standards process. Understanding DS Protocol requires clarity about what it is not: it is not a token interface standard in the way ERC-7943 or ERC-3643 are. It is a full-stack platform architecture — token issuance mechanics, investor identity management, transfer agent workflow, and secondary market connectivity — that Securitize has built and operates as a commercial service.
Securitize's approach reflects a deliberate philosophy that differs from open standards advocates. Rather than defining an interface that others can implement, Securitize built a proprietary stack optimized for the specific regulatory requirements of US exempt securities — Regulation D, Regulation A, and Regulation S — and for connectivity to their own alternative trading system. The DS Protocol tokens are interoperable with Securitize's broker-dealer and transfer agent infrastructure by design, because both were built by the same organization with the same regulatory objectives.
Commercially, this has been effective. Securitize has assembled the largest portfolio of institutional tokenized security deployments in the United States. Clients include KKR, Hamilton Lane, and Apollo. The firm serves as transfer agent and has facilitated the tokenized share class for BlackRock's BUIDL fund on Ethereum, among others. The Securitize platform handles issuance, cap table management, investor accreditation verification, secondary market matching through their ATS, and distributions — an end-to-end service that open standards, by definition, cannot offer.
The tradeoff is portability. DS Protocol tokens are designed to operate within the Securitize ecosystem. If an issuer decides to move to a different transfer agent, if Securitize's regulatory standing changes, or if secondary market access needs to expand beyond their ATS, the migration path is non-trivial. This is the characteristic cost of proprietary platform lock-in, and it is an appropriate concern for issuers with long-duration securities — particularly those with ten or twenty-year hold periods.
The absence of public technical documentation on DS Protocol internals limits independent due diligence. There is no EIP, no publicly audited interface specification, and no community of independent implementers. Issuers evaluating DS Protocol are evaluating a service provider relationship as much as a technical architecture — and should assess accordingly.
Technical Specification
The DS Protocol (Digital Securities Protocol) is Securitize's proprietary smart contract and compliance infrastructure for issuing and managing tokenized securities on Ethereum and Polygon. It is not submitted as an EIP and has no public interface specification. The following is derived from Securitize's published materials, developer documentation, and observable on-chain behavior.
ARCHITECTURE OVERVIEW (publicly described)
DS Protocol is a layered architecture:
1. DS Token — ERC-20-compatible token with transfer restrictions
2. DS Registry — investor identity and eligibility database
3. DS Compliance — rule engine for transfer eligibility
4. DS Service Object — tracks permissioned service providers
DS TOKEN
The DS Token contract is ERC-20 compatible with additional gating:
- transfer() and transferFrom() invoke compliance checks before execution
- Transfers between unregistered or non-compliant addresses revert
- Authorized operators (Securitize's systems) can perform forced transfers
- Token contracts are non-upgradeable by default; changes require new deployment
with migration tooling managed by Securitize
DS REGISTRY
The investor registry is Securitize's proprietary KYC/AML database:
- Investors complete accreditation verification through Securitize's onboarding portal
- Verified investors receive an on-chain allowance tied to their wallet address
- Off-chain identity data is maintained in Securitize's compliance systems
- The on-chain component is a mapping of wallet → eligibility status (boolean/flags)
This differs fundamentally from ONCHAINID: there is no portable investor identity
contract. The eligibility record is Securitize-controlled and Securitize-specific.
DS COMPLIANCE ENGINE
Rule evaluation is handled server-side with on-chain enforcement:
- Transfer eligibility is computed off-chain against Securitize's rule database
- The result is reflected as an on-chain allowance or permission flag
- Rules include: Reg D 12-month holding period, Reg S offshore investor status,
investor count limits (Rule 506(b) 2,000 investor cap), AML screening
- Some rules are enforced entirely on-chain (frozen addresses), others require
Securitize operator intervention to update
SECONDARY MARKET (ATS)
Securitize Markets (formerly MERJ exchange partnership, now Securitize's own ATS)
is tightly integrated with DS Protocol. The ATS can read DS Registry eligibility
and DS Token transfer permissions directly, enabling same-day settlement for
eligible investor-to-investor secondary trades. This tight integration is a genuine
operational advantage that no open standard provides natively.
CHAIN SUPPORT
Primary: Ethereum (most institutional issuances)
Secondary: Polygon (lower gas cost deployments, some fund products)
Not confirmed: other EVM chains. Securitize selects chain per issuance context.
GOVERNANCE
Fully proprietary. Securitize controls all protocol changes. No external contributors.
No public roadmap beyond marketing materials. Changes are deployed at Securitize's
discretion. Issuers have no mechanism to influence protocol evolution.
REGULATORY STANDING
- Securitize is a SEC-registered transfer agent
- Securitize Markets LLC is a FINRA-registered broker-dealer and ATS operator
- These regulatory registrations are meaningful governance substitutes for open-source
auditing: regulators can examine Securitize's books and practices
- The proprietary nature of the protocol is therefore partially offset by regulatory
oversight of the operating entity
LIMITATIONS ON PUBLIC DOCUMENTATION
Securitize has not published a formal technical specification for DS Protocol.
Developer documentation covers API endpoints for issuance and cap table management.
Smart contract ABIs and source code are not publicly available for independent audit.
This limits technical due diligence to observable on-chain behavior and published
marketing and regulatory filings.
Key Features
Full-stack service: single provider for token issuance, KYC/AML, cap table management, transfer agency, and ATS secondary marketUS regulatory standing: Securitize is an SEC-registered transfer agent and FINRA-registered broker-dealer, providing regulatory assurance beyond technical auditInstitutional client roster: KKR, Hamilton Lane, Apollo, BlackRock BUIDL fund — production deployments at institutional scaleIntegrated ATS: tight connectivity between DS Protocol tokens and Securitize Markets enables compliant secondary trading without third-party integrationProven US exempt securities deployment: optimized for Reg D, Reg A, and Reg S compliance frameworks specifically
US Regulatory Fit
DS Protocol is the strongest fit for US securities regulatory requirements of any standard covered in this survey — primarily because Securitize operates as a SEC-registered transfer agent and FINRA-registered broker-dealer, making the protocol's regulatory compliance largely a function of Securitize's own regulatory standing rather than abstract technical specifications. The investor accreditation process is designed specifically around SEC exemptions: Regulation D Rule 506(b) and 506(c), Regulation A, and Regulation S. The system enforces the 12-month holding period for Reg D securities, tracks the 2,000 investor cap for 506(b) issuances, and maintains records in forms consistent with SEC examination requirements. EDGAR integration, DTC connectivity for any cross-system settlement, and regulatory reporting are handled within Securitize's transfer agency operations rather than by the protocol itself. The cost of this regulatory clarity is the absence of technical openness — issuers accepting DS Protocol are accepting Securitize as their transfer agent, and all the dependencies that come with that relationship.
Institutional Adoption
DS Protocol has the largest US institutional deployment portfolio of any tokenization approach covered in this survey. Verified deployments include: KKR Health Care Strategic Growth Fund tokenized share class; Hamilton Lane SCOPE (Senior Credit Opportunities Private Fund) tokenized feeder; Apollo Diversified Credit Securitize Fund; BlackRock USD Institutional Digital Liquidity Fund (BUIDL) on Ethereum, where Securitize serves as transfer agent. In aggregate, Securitize has reported managing over $1 billion in tokenized assets under administration as of 2024, across more than 30 issuances. Their ATS has facilitated secondary market transactions for Reg D securities among accredited investors. Securitize has also partnered with fund administrators and custodians including Bank of New York Mellon for certain custody arrangements, lending institutional credibility to the infrastructure.
Limitations & Trade-offs
Fully proprietary: no public interface specification, no independent audit path, no community of independent implementersVendor lock-in: migrating off DS Protocol requires Securitize's cooperation and is non-trivial for long-duration securitiesNo identity portability: investor eligibility is Securitize-controlled; investors cannot carry their compliance record to other platformsLimited chain support: Ethereum and Polygon only; no confirmed path to other chains or cross-chain architecturesService dependency: the value proposition depends on Securitize's ongoing operation — regulatory issues, acquisition, or business failure would directly impact all issuances