Read the original proposal on Discourse
LDO does not have an elastic supply or rebase mechanism. The token contract appears to implement the standard MiniMe Token 1.
LDO currently has a 1,000,000,000 fixed supply of which 24,539,272 are circulating 1. The contracts and addresses with the highest concentration of LDO tokens are the DAO treasury (rank 1), Lido Dao Vault Contract (rank 2), paradigm capital 3 given the recent wallet history and purchase 3 (rank 3), Founder's wallet (given that they received ~50M each in tokens and its age) (rank9), and Proxy Contracts (rank 4, rank5, rank6, rank 7, rank 8, rank 10).

Lido is a staking solution for ETH 2.0 backed by several industry-leading staking providers. It makes staked ETH liquid and allows participation with any amount of ETH.
When using Lido to stake your ETH on the Ethereum beacon chain, users will receive a token (stETH), which represents their ETH on the Ethereum beacon chain on a 1:1 basis. It effectively acts as a bridge bringing ETH 2.0's staking rewards to ETH 1.0.
As a user's staked ETH generates staking rewards from ETH 2.0, the user's ETH balance on the beacon chain will increase. stETH balances will update correspondingly once per day allowing you to access on ETH 1.0 the value of your staking rewards received on ETH 2.0.
Users can use stETH in all of the same ways that they can use ETH: sell it, spend it and, since it is compatible to be used in DeFi, use it as collateral for on-chain lending. When transactions are enabled on ETH 2.0, users can also redeem stETH for ETH.
The LDO token is the governance token for Lido DAO. It is used to vote on protocol parameters and govern the constantly growing Lido DAO treasury.
Upon the launch of the Lido DAO, 1 billion LDO tokens were minted. Founding members of the Lido DAO received 64% of LDO tokens. These tokens are locked for one year, after which they will vest over the following year.
The allocation of LDO tokens is as follows:
LDO holders that participate in the DAO have the following responsibilities:
Lido raised $2 million in a Dec. 2020 round backed by Semantic Ventures, ParaFi Capital, Terra, KR1, Stakefish, and Staking Facilities, among others. Angel investors, including Rune Christensen of MakerDAO, Stani Kulechov of Aave, and Kain Warwick of Synthetix, also participated in the round.
Lido also recently (May 2021) raised $73 million in a round 3 led by paradigm capital.
The Lido team operates an official Twitter, Blog, and Reddit account. The repositories for their code is hosted on GitHub. There is a Telegram and Discord channel that is available to their community. The official documentation is hosted on GitHub. There is also a governance forum that's available to their community members.
There are three audits available from different firms for Lido:
Quanstamp 2
Sigmaprime 2
MixBytes 2