Yield
Defunct1 known investors
Ethereum DeFi protocol for collateralized fixed-rate, fixed-term borrowing and lending that wound down at the end of 2023.
Also known as Yield · Yield Protocol
Investors · 1
Company profile
researched Aug 2026Yield Protocol was an Ethereum-based decentralized finance protocol providing collateralized fixed-rate, fixed-term borrowing and lending, positioned as an alternative to the predominantly floating-rate DeFi lending protocols whose interest rate volatility complicates planning and hedging. The protocol's core primitive was the fyToken (fixed yield token), an ERC-20 token redeemable one-to-one for an underlying asset after a predetermined maturity date; for example, one fyDai is redeemable for one Dai at maturity. fyTokens pay no interest and instead trade at a discount to redemption value, behaving like zero-coupon bonds, with the implied interest rate derived from the difference between the discounted price and the face value at maturity. The design drew on the paper "The Yield Protocol: On-Chain Lending With Interest Rate Discovery" by Dan Robinson and Allan Niemerg [3][5].
The system comprised debt vaults (vault-v2), liquidity-providing strategies (strategy-v2), and YieldSpace, a purpose-built automated market maker for trading fyTokens and tokenized vault tokens, alongside a web application front end and public documentation [0][3][5]. Products were organized into dated fixed-rate series (for example, the March-September strategies and the December 2023 series) that matured on set dates [6]. The protocol did not have a governance token; maintenance and development were carried out by the founding development team, which stated an intention to move toward community ownership through progressive decentralization [3].
In October 2023 the team announced a permanent wind-down, cancelling the planned March 2024 series and ending all borrowing and lending by December 31, 2023 [6]. Public sources also list a separately branded ERC-20 token called "Yield Protocol" (ticker YIELD) described as an open-source yield-farming strategy platform; that listing is tagged as inactive and its stated website differs from yieldprotocol.com [1][2][4].
Founding story
Sources do not describe the founding of the company. The protocol design was inspired by the paper "The Yield Protocol: On-Chain Lending With Interest Rate Discovery" by Dan Robinson and Allan Niemerg, and the team acknowledged feedback from Dan Robinson, Georgios Konstantopoulos and Sam Sun (Paradigm), Mikhail Vladimirov (ABDK), Gustavo Grieco (Trail of Bits), Martin Lundfall (dAppHub) and Noah Zinsmeister (Uniswap) [5].
Business model
Yield Protocol operated as an on-chain, permissionless protocol rather than a conventional service business. Users borrowed and lent at fixed rates for fixed terms against collateral, trading fyTokens through the YieldSpace AMM, with liquidity providers accruing fees on the protocol's dated strategies [3][6]. Sources do not describe a fee-to-treasury or corporate revenue arrangement.
Available sources describe fees accruing to liquidity providers on Yield's strategies but do not detail protocol or company revenue capture [6].
Traction
Public evidence of traction is limited. The protocol shipped v1 and v2 contract suites deployed to Ethereum mainnet and Kovan with a web frontend, and ran successive dated fixed-rate series through December 2023 [5][6]. Its most-starred public repository, vault-v2, had 162 stars [0]. The team stated there was not sustainable demand for fixed-rate borrowing on the protocol at the time of the wind-down [6].
Latest developments
Following the October 2023 wind-down announcement and the December 31, 2023 end of borrowing and lending, public GitHub activity tapered off: the app-v2 UI was last updated in February 2024, the cacti-backend and bot_platform repositories in March 2024, the yield-web website repository in October 2024, and a repository named 'closed' in November 2024 [0][6].
▸Full profile — market position, technology, go-to-market, geography, history, risks & controversies
Market position
Yield Protocol was a DeFi lending protocol focused specifically on fixed-rate, fixed-term markets, a segment it contrasted with the floating-rate design of most major DeFi lending protocols [3]. Its shutdown was attributed to insufficient sustainable demand for fixed-rate borrowing on the protocol [6].
Fixed-rate, fixed-term lending via zero-coupon-style fyTokens with a dedicated AMM (YieldSpace) tuned for interest-rate discovery, in contrast to floating-rate DeFi lending markets; the codebase was subjected to multiple third-party audits and fuzz testing [3][5].
Technology
Solidity smart contracts on Ethereum, organized into debt vaults (vault-v2), liquidity strategies (strategy-v2) and the YieldSpace AMM for fyTokens and tokenized vault tokens; a TypeScript web application (app-v2) and Docsify-based documentation site accompanied the contracts [0][3]. fyTokens are ERC-20 zero-coupon-style tokens redeemable one-to-one for an underlying asset at maturity [3]. Development used Buidler, Truffle, Ganache and Echidna fuzz testing, with both decimal- and binary-based fixed-point math libraries for the YieldSpace formula [5]. Contracts were audited by Trail of Bits, Code 423n4 and (for YieldSpace TV) ABDK Consulting, and the project ran an Immunefi bug bounty offering up to $250,000 for v2 (up to $50,000 under the earlier v1 program) [3][5]. Later repositories included non-core experiments such as cacti-backend, described as natural-language interactions with web3, and deep-cookie, described as an LLM Solidity gym [0].
Go-to-market
Distribution was through a self-serve web dapp and public smart contracts, supported by developer documentation, a GitHub organization, a Discord community, Twitter and Medium channels, and an Immunefi bug bounty program [0][3].
DeFi borrowers and lenders seeking predictable fixed interest rates and fixed terms, liquidity providers supplying capital to dated strategies, and developers integrating the smart contracts [3][6].
Geography
Sources do not state a headquarters or offices; the protocol operated on public Ethereum networks (mainnet and the Kovan testnet) and cited regulatory conditions in the United States, Europe and the United Kingdom as a factor in its shutdown [5][6].
History
Yield Protocol's v1 implementation (YieldToken/YieldSpace v1) was deployed to Ethereum mainnet and Kovan with a frontend at app.yield.is, and was audited by Trail of Bits [5]. A v2 architecture followed, comprising vault-v2 debt vaults, strategy-v2 liquidity strategies and the YieldSpace TV AMM, documented in docs-v2 and audited by ABDK Consulting, Code 423n4 and Trail of Bits [0][3]. On October 3, 2023 the team announced the wind-down; the March 2024 series was cancelled and borrowing and lending ended December 31, 2023 [6]. Repository activity in the organization continued into 2024, including a repository named 'closed' last updated in November 2024 [0].
Risks & controversies
The protocol ceased operations at the end of 2023, with the team citing a lack of sustainable demand for fixed-rate borrowing and unfavorable crypto regulation in the United States, Europe and the United Kingdom [6]. Users were required to close positions, and a dedicated repository was published to allow closing Yield Protocol positions through Etherscan without the frontend [0]. Note also potential name confusion with a distinct ERC-20 token branded "Yield Protocol" (YIELD) tracked by crypto price aggregators and tagged inactive, whose listed website is yieldprotocol.org [1][2][4].
Compiled by commissioned research from 8 cited public sources — announcements, filings, and press listed under research sources below.
Key figures
latest reportedCompany-reported or press-reported figures, each dated to when it was claimed — not independently audited.
Timeline · 2
launches, deals, and filingsThe December 2023 series matured on December 29, 2023 and all borrowing and lending on the protocol ended by December 31, 2023.
Yield Protocol announced it would wind down permanently, cancelling the March 2024 fixed-rate series and leaving only the December 2023 series active. The team cited a lack of sustainable demand for fixed-rate borrowing and unfavorable crypto regulations in the US, Europe and the UK.
Dated company events from announcements, filings, and press; legal rows summarize public dockets and regulator releases.
▸Research sources · 8
primary sources listed
- Yield Protocol · GitHubgithub.com · web
8 public sources were cited for this profile; the first-party ones are listed here.
Frequently asked questions
- What does Yield do?
- Ethereum DeFi protocol for collateralized fixed-rate, fixed-term borrowing and lending that wound down at the end of 2023.
- Who are Yield's investors?
- Yield's investors include Paradigm.