Bitcoin is a $1.68 trillion asset. Yet it still has no native interest rate. A report from Alea Research, translated by TechFlow, says Stacks’ Genesis Bond is trying to change that: the yield is paid in BTC, the position is priced in BTC, and the underlying coins stay under the holder’s own key control.
The structure targets a 3% annualized BTC yield and has been making weekly payments since Sept. 17. That is what separates it from other Bitcoin finance protocols named in the report, including Core and Babylon, which reward stakers in CORE and BABY instead of Bitcoin itself. Genesis Bond does the opposite. It pays BTC on the 230.17 BTC already bonded.
The report also says STX ended September at $0.3715, above its 90-day average and triple its August low.
A BTC-paying bond that keeps Bitcoin on Bitcoin rails
By Sept. 30, applications on Bitcoin had logged $4.47 billion in deposits, or just 0.27% of the asset’s value, the report says. Most idle BTC still earns nothing unless holders lend it out or lock it up for rewards paid in some other token. Alea Research’s view is blunt: Bitcoin DeFi often leaves depositors with an incentive token they may not even want.
Stacks rolled out PoX-5, its Bitcoin staking upgrade, on July 30. Under the setup described in the report, holders lock BTC in a standard Bitcoin timelock and keep control of their keys, then match that position with STX worth at least 5% of the position value. Each bond cycle runs about 175 days. SIP-045 backs a 3% annual target yield, paid weekly in BTC. Holders of sBTC, the Bitcoin-backed token on Stacks, can bond through the same framework too.
Smaller participants have another route. The report points to StackingDAO’s stBTC, which carries an estimated net BTC yield of 2.4% and does not require the user to hold STX directly.
Alea Research calls the native bond the only path that keeps Bitcoin under the holder’s own keys. stBTC, on the other hand, is described as the only path with no STX price exposure.
At maturity, the bonded Bitcoin comes back in full, and neither leg faces slashing. Getting out early needs a jointly signed release from a designated signer set. But there is a catch. That only unlocks the Bitcoin sooner. The holder gives up the remaining yield, while the STX leg stays locked until the original maturity date.
Miners fund the rate, and bonds get paid first
Stacks miners spend BTC to compete for the right to produce Stacks blocks. Winners get newly minted STX block rewards and transaction fees. Under SIP-045, the block reward per Bitcoin block was restored from 500 STX to 1,000 STX, and all BTC spent by miners is sent into a reward pool. Bonds get their 3% claim first. Then, of what is left, 85% goes to STX-only stackers and 15% goes to reserves.
The report says the launch phase is, in effect, funded by newly issued STX. Holders are covering the bootstrap period through dilution, while fees are still a secondary and fairly small source of miner revenue. The network also approved a separate treasury issuance in SIP-031 to fund the Stacks Endowment, which manages the launch phase.
One chart in the report shows fees making up 3.5% of miners’ $18.2 million annualized revenue, with the rest coming from coinbase.
Another chart shows daily miner revenue tracking the STX price, while fees stayed in a tight band through the August low and the September rebound.
The PoX-5 contract recorded 1.90 BTC in reserves on Oct. 1. During the bootstrap phase, those reserves are still growing. SIP-045 requires a consensus change before the reserve can be tapped. If miners pay less than what bondholders are owed, the shortfall hits STX-only stackers first. If coverage drops below 1.5x, new bond size is cut. If it falls below 1.0x, the protocol pauses new bonds, and reserves then cover the gap.
First month: 230.17 BTC bonded and weekly payments underway
Stacks launched Genesis Bond on Sept. 10 at Bitcoin block 966,350. Four institutions participated: UTXO Management, Sypher Capital, 21Shares, and HashKey. Muneeb Ali, who became chief executive of Stacks Labs on Sept. 30, said each institutional partner used its full allocation. He said the bond rate “could become Bitcoin’s version of the federal funds rate.”
The report also says StackingDAO’s 150 BTC pool had already closed before the bond opened.
Demand showed up through two channels at the same time. Bond 1 in the PoX-5 contract holds 230.17 BTC, split between 70.00 BTC in native Bitcoin timelocks and 160.17 BTC in sBTC, most of it through StackingDAO. Weekly payments started on Sept. 17. After that, StackingDAO updated the estimated net yield on stBTC to 2.4% after pool fees. On Sept. 24, Stacks said Anchorage Digital had joined as bond custodian, alongside Fireblocks and Fordefi.
One chart in the report shows StackingDAO holding 161.20 sBTC, second only to Zest V2 among Stacks applications.
The PoX-5 contract recorded a 4.93 BTC reward pool in cycle 143. Cycle 139 was the last full cycle under PoX-4, when 2.79 BTC was paid to stackers. That means the reward pool is up 77.0%.
STX is the capacity asset, and each bond locks STX beside BTC
SIP-045 set the initial launch conditions at 3,000 BTC of capacity and a 3% target annual yield. The report is clear on one point: this is not a fixed cap for the first year. The Stacks Endowment sets capacity for each bond window, and Stacks plans to expand issuance as miner bids increase. Available size depends on miner economics, including the STX/BTC exchange rate and the coverage needed to support bond payments.
At that initial reference size, annual bond payments would total 90 BTC. In cycle 143, the reward pool annualized to 128.2 BTC, equal to 1.4x coverage, versus 0.8x before the fork. The report says the payment and coverage math keeps the bond book at that reference size, while future capacity will be set window by window.
The chart shows annualized miner-settled Bitcoin at 128.2 BTC in cycle 143, above the 90 BTC annual coupon obligation implied by the initial reference size.
On the report’s math, the pool can still absorb nine Genesis Bonds. Coverage on the first one stands at 18.6x. SIP-045 set a 2.0x coverage target, and at that level the cycle 143 pool could support about 2,140 BTC of bonds.
Alea Research ties the larger pool to three factors. First, PoX-5 restored coinbase to 1,000 STX and, under SIP-045, redirected BTC that had been burned under PoX-4 into the pool. Second, STX/BTC rose 105.5% between the July 30 fork and the Sept. 30 close. Third, miners bid in BTC based on the value of coinbase, so a stronger STX/BTC rate pulls more miner BTC into the pool.
One chart rebases prices to 100 at the fork and shows STX at 265 by the end of September, versus 129 for Bitcoin.
The report adds that, with the bond book kept at the initial reference size, a 30% drop in STX/BTC would push coverage down to 1.0x at observed coinbase levels, while a 40% rise would lift it to the 2.0x target.
Every bonded BTC needs STX next to it. That is the link between Bitcoin demand and the token. The contract records the Genesis Bond reference value at 310,237 STX per BTC, locking 3.57 million STX in total. That equals 0.8% of the 448.3 million STX stacked in cycle 144. Each new bond turns Bitcoin demand into STX demand using the ratio set by the Endowment for that window.
The main risk for bondholders sits in the STX leg
STX closed Sept. 30 with a $695 million market capitalization, 10.9 times the size of BABY, the token tied to Babylon’s Bitcoin staking protocol. STX-only stackers hold the residual claim on the reward pool and were earning a 6.0% annualized BTC-denominated return in the last settlement cycle. Every bond registered ahead of them increases the senior claim on that same pool.
The bond pays a 1.44% coupon over its 175-day term. Because the STX sidecar makes up 5% of the position and is marked in BTC at maturity, every 20% drop in STX/BTC cuts 1% from the position. A 28.8% decline wipes out the full coupon.
The report says that since October 2021, 51.8% of 1,651 overlapping 175-day windows saw STX/BTC fall by 28.8% or more. In the hedged version, the bond still delivers the 1.44% coupon across all paths.
The Bitcoin principal itself does not decline with STX. One bonded BTC still returns one BTC at maturity. The report gives two ways to remove the sidecar risk: short an equal amount of STX to lock in the 1.44% return across all paths, or hold stBTC, where StackingDAO pairs the bond with STX it has already stacked and keeps part of the rewards.
Bonded BTC is moving into the Stacks application layer
StackingDAO’s stBTC turns the bond into collateral, and Zest, which holds most of the Bitcoin in Stacks applications, already accepts it, according to the report. Zest’s Bitcoin-backed vault went live on Sept. 23. Stack Sats, a rewards program, said it will distribute 1 BTC per week to Zest and Bitflow users through Dec. 10.
A chart in the report shows Bitcoin held across Stacks applications rising to 1,013 BTC by the end of September, 18% below the peak reached in May 2026.
Stacks’ roadmap also adds lending against Bitcoin that remains in timelock. Under that design, vaults holding native bonds would be able to borrow without moving the underlying BTC.
Second bond window opens Oct. 10
Stacks has set Oct. 10 for the second bond issuance window. Contract terms already recorded on-chain show a 3% target yield and pricing of 267,384 STX per BTC. Ali said Stacks “may release greater Bitcoin capacity for the second bond.” Under SIP-045, about 10% of each window’s capacity is allocated to a public pool on a first-come, first-served basis.
Alea Research’s takeaway is pretty direct: Stacks is trying to build a BTC-funded, BTC-paying yield mechanism for Bitcoin holders while leaving the coins under their own control. One month in, the first bond has raised 230.17 BTC and weekly payouts are already running. Starting Oct. 10, each new window is set to convert more miner BTC into yield that can sit inside vaults.