1. Regulatory and Legal Constraints

Tokenized stock issuers generally avoid using blockchain as the sole, direct shareholder record due to a "mandatory hybrid model" imposed by regulatory requirements, privacy constraints, and operational complexities. While state laws in jurisdictions like Delaware permit blockchain-based record-keeping, federal SEC mandates currently require these records to be reconciled with traditional off-chain systems.

1. Regulatory and Legal Constraints

The primary driver for avoiding direct on-chain records is the SEC Transfer Agent Requirement under Section 17A of the Exchange Act.

• Mandatory Reconciliation: The SEC requires that on-chain records be "rigorously reconciled" with off-chain records to ensure legal title remains accurate [Source: https://www.sec.gov/news/statement/joint-staff-statement-tokenized-securities].
• Master Securityholder Files: Issuers must maintain a "master securityholder file" containing Personally Identifiable Information (PII) such as names and physical addresses. Storing this data directly on a public blockchain would violate global privacy laws (like GDPR), forcing issuers to keep the authoritative record off-chain.
• The "Notification" Model: Many issuers treat tokens as mere "transfer triggers." The token itself conveys no legal rights; it simply signals the off-chain registrar to update the official books [Source: https://www.sec.gov/comments/tokenization-rulemaking].

2. Operational and Compliance Challenges

Maintaining a direct registry on-chain introduces significant technical friction that often outweighs the benefits of decentralization.

• Corporate Action Complexity: Processing dividends, stock splits, and voting for the roughly 3.7 million annual corporate action events in the US market is technically difficult to automate on-chain [Source: https://www.weforum.org/reports/digital-assets-2026].
• Identity Mapping: Because wallet addresses do not satisfy "Know Your Customer" (KYC) requirements, issuers must maintain a 1:1 mapping of every wallet to a verified legal identity. This creates a "redundant and costly" administrative burden [Source: https://www.sec.gov/comments/tokenization-rulemaking].
• Liability and "Fiduciary Leakage": Issuers fear legal liability for blockchain-specific failures, such as smart contract bugs or investors losing private keys, which could lead to disputes over the "true" ownership of the underlying stock.

3. Comparison of Record-Keeping Models

4. Structural Workarounds: The Nominee Model

To satisfy securities laws while utilizing blockchain infrastructure, most issuers use an indirect or nominee structure:

• The Wrapper Approach: A Special Purpose Vehicle (SPV) or custodian holds the actual shares and issues tokens representing a beneficial interest in those shares.
• Centralized "Golden Record": To prevent "double-counting" across multiple chains (e.g., Ethereum and Solana), issuers maintain a centralized off-chain record that acts as the single source of truth, regardless of where the token is traded [Source: https://www.dtcc.com/news/2026/march/tokenization-report].

Summary of Legal Permissions

Despite the federal hurdles, state-level legislation has been proactive. Section 224 of the Delaware General Corporation Law (DGCL) expressly permits corporations to use blockchain for corporate record-keeping and share issuance, a change enacted in 2017 [Source: https://corp.delaware.gov/dgcl/]. However, until federal SEC rules evolve to recognize blockchain as a standalone "master securityholder file," issuers will continue to prioritize indirect, reconciled records over direct on-chain registries.

Next Steps:

• Would you like a deep dive into the specific smart contract standards (like ERC-3643) used by issuers to enforce these off-chain KYC requirements?
• I can also research the current SEC "Sandbox" initiatives that might allow for native on-chain settlement in the future.