# BlackRock BUIDL Fund: Supply, Chains and Holders

> BlackRock BUIDL tracker: tokenized money market fund shares outstanding by chain, dividend share mints, holders and the protocols holding BUIDL, read on-chain.

Markdown copy of https://voltfincrypto.com/apps/blackrock-buidl-fund-tracker

**Question:** How many BUIDL shares are outstanding, on which chains and who holds them?

- Kind: Dashboard in Voltfin Vantage
- Topic: [Tokenized assets](https://voltfincrypto.com/topics/rwa)
- Chains: Multi-chain, Ethereum, Solana, Aptos, Arbitrum, Avalanche, OP Mainnet, Polygon, BNB Chain
- Status: Planned. The data is not published yet, so this page states no figure; each figure will open its receipt when it is.

BUIDL is the BlackRock USD Institutional Digital Liquidity Fund, a money-market fund whose shares are issued as tokens through Securitize. It invests in cash, US Treasury bills and repurchase agreements, keeps a stable value per share and pays its income as new tokens. This dashboard reads the shares outstanding from the token contract on every chain BUIDL is issued on, so its size and chain split come from the chains themselves.

Only approved investors can hold BUIDL, and many of its largest holders are other protocols' contracts: stablecoin reserves, fund tokens and collateral vaults that hold BUIDL for their own users. The holders page labels those contracts where a public source supports the label, which shows how much of the fund sits behind other on-chain products.

Use it to follow the fund's size and chain split, to see how income distributions add to supply and to check which protocols hold it. Every figure is pinned to the block it was read at on its chain, with the call or log behind it.

## Blueprint

### Supply

Shares outstanding by chain and how they changed.

- **Shares outstanding** (shares): BUIDL tokens outstanding across every chain at the latest day-end blocks.
- **30-day change** (%): Change in shares outstanding against thirty days earlier, across every chain.
- **Latest income distribution** (shares): Shares minted to holders in the latest income distribution, summed across chains.
- **Share on Ethereum** (%): Share of BUIDL supply on Ethereum, the chain it launched on.
- **Shares outstanding by chain** (shares): Shares outstanding on each chain at each day-end block since launch.

### Holders

Who holds BUIDL, by address and by protocol.

- **Holders** (count): Addresses holding BUIDL across every chain at the latest blocks.
- **Top 10 holders' share** (%): Share of supply held by the 10 largest addresses.
- **Supply by holder type** (shares): Supply split between labelled protocol contracts (stablecoin reserves, fund tokens, collateral vaults) and other addresses.
- **Largest holders**: The largest holders with their chain, balance, share of supply and label where a public source supports one.

Filters: Chain (Every chain BUIDL is issued on, or one of them); Period (Last 30 days, last year or since launch).

## How it will be measured

- Shares outstanding are BUIDL's totalSupply() on each chain at the last block of each day, scaled by decimals; tokens locked in a cross-chain transfer contract while copies circulate elsewhere are taken out, so no share is counted twice.
- Income distributions are the share mints to holders on distribution dates, read from Transfer logs from the zero address and told apart from subscriptions because they go to many holders in proportion to their balances.
- Holders are addresses with a non-zero balance rebuilt from Transfer logs and checked against balanceOf; a contract is labelled only when a public source names the protocol behind it.
- Value uses the stable value per share stated in the fund's documents, an off-chain input recorded with its source.
- Every figure carries a receipt: the chain, the block, its hash and the calls behind it.

## Data it needs

- `rwa_supply_daily` (to build): Supply and holders of tokenized treasuries, money-market funds, stocks, gold and credit per token and chain per day, with issuer and asset class.
- `token_holders_snapshot` (to build): Holder counts, top holders and concentration shares of registry tokens at a pinned block, with contract and exchange labels.
- `address_labels` (to build): Labels for known addresses: exchanges, bridges, protocols, funds, treasuries, sanctioned addresses and known attackers.
- `token_transfers_daily` (to build): ERC-20 and native transfer counts, volume and unique senders and receivers per token per chain per day.
- Source: BUIDL totalSupply() and Transfer logs on each EVM chain at day-end blocks
- Source: BUIDL supply on Solana and Aptos through their own token programs (scaffolds)
- Source: Dividend share mints to holders on distribution dates
- Source: Holder addresses with labels for DeFi vaults, fund tokens and stablecoin reserves
- Source: The stable value per share stated in the fund's documents (off-chain)

## Questions

### What is BlackRock's BUIDL fund?

BUIDL is a tokenized money-market fund launched by BlackRock in March 2024, with Securitize as its tokenization platform and transfer agent. It holds cash, US Treasury bills and repurchase agreements, and its shares exist as tokens that approved investors can hold and transfer on-chain.

### Which chains is BUIDL on?

BUIDL started on Ethereum and has since been issued on other chains, including Aptos, Arbitrum, Avalanche, OP Mainnet, Polygon, Solana and BNB Chain. The chain split tile shows the supply on each, read from each chain's own token contract.

### How does BUIDL pay dividends?

BUIDL keeps a stable value per share and pays its income by minting new BUIDL tokens to holders on each distribution date, so a holder's balance grows instead of the price. The supply page reads those mints from the chain.

### Who can hold BUIDL?

Only investors approved by Securitize, which keeps an allowlist that the token contract checks on every transfer. Many holders are institutions and other protocols' contracts; this dashboard counts addresses and labels known contracts, and does not identify people.

### Why does BUIDL's size change?

Shares are created when investors subscribe and destroyed when they redeem, and each income distribution adds new shares. Large moves often come from a few big holders, such as protocols moving reserves in or out, which the holders page shows.

## Glossary

- **Money-market fund**: A fund that holds cash and short-term government debt and aims to keep a stable value per share while paying income.
- **Transfer agent**: The firm that keeps a fund's register of shareholders; for BUIDL, Securitize, whose token contracts serve as that register on-chain.
- **Allowlist**: The list of approved addresses a permissioned token checks before it allows a transfer.

## Related apps

- [Tokenized Treasuries Tracker: BUIDL, BENJI, USYC, OUSG](https://voltfincrypto.com/apps/tokenized-treasuries-tracker)
- [Tokenized Treasuries by Fund and Chain](https://voltfincrypto.com/apps/tokenized-treasuries-table)
- [Tokenized Treasury Fund Yields](https://voltfincrypto.com/apps/tokenized-treasury-fund-yields)
- [Tokenized RWA Market Size by Chain](https://voltfincrypto.com/apps/tokenized-rwa-market-size-by-chain)
- [Tokenized Gold Supply: XAUT vs PAXG](https://voltfincrypto.com/apps/tokenized-gold-xaut-paxg)
- [Tokenized Stocks Market Cap by Issuer and Chain](https://voltfincrypto.com/apps/tokenized-stocks-market-cap)

Build it in Voltfin Studio: https://app.voltfincrypto.com/signup?next=%2F