How Pendle Principal Tokens Turn a Discount Into a Maturity Return

A Pendle principal token, or PT, can lock in a return by costing less than the asset value it is redeemable for at maturity. For an unleveraged holder, that return is measured in the market’s accounting asset—not necessarily dollars—and selling early replaces the maturity payoff with a market price.

Pendle splits yield-bearing assets into two claims: PT represents principal redeemable after maturity, while the yield token, YT, receives the underlying yield until that date. PT holders forgo that variable yield and associated points; their return instead comes from the purchase discount.

The mechanism underpins Sky’s Fixed Yield product, covered in The Defiant’s June 4, 2026 launch report. Sky’s disclosure says its Pendle-based rate is market-set and that an early sale can fetch more or less than the entry price.

From Purchase Discount to Redemption

The unit matters. Pendle’s PT documentation uses PT-ezETH ($ETH): under normal redemption conditions, one PT represents one $ETH’s worth of ezETH at maturity, **not one ezETH**. $ETH is the accounting asset; ezETH is the token backing the claim.

Consider a hypothetical purchase of **100 PT for 95 $ETH-equivalent**, with 365 days remaining. All prices, exchange rates and costs below are illustrative, not market quotes. Assume normal redemption and intact backing.

The gross maturity value is 100 $ETH-equivalent, giving a 5 $ETH gain on the 95 $ETH purchase price: **5.26% over the year**. Using Pendle’s annualization method, for a PT redeemable for one accounting unit:

**Implied annualized yield = (1 ÷ PT price)^(365 ÷ days remaining) − 1.**

The price must be expressed in accounting units per PT. A 5% discount to redemption value is therefore not the same as a 5% return on purchase cost. The same discount over a shorter period implies a higher annualized yield, not a larger total payout.

Add an assumed 0.2 $ETH entry cost: total outlay becomes **95.2 $ETH-equivalent**. At maturity, if one ezETH is worth 1.10 $ETH, the 100 PT claim corresponds to approximately **90.91 ezETH**, worth 100 $ETH before costs. Deduct an illustrative 0.1 $ETH redemption network cost and net value is **99.9 $ETH-equivalent**, a **4.7 $ETH-equivalent gain**. Any conversion into another asset is separate from the underlying redemption.

An Early Sale Changes the Accounting

Now suppose the holder sells halfway through, with **182.5 days remaining**. The following ledger keeps that remaining term identical across the two early-sale scenarios and compares net value with the same 95.2 $ETH-equivalent initial outlay. Assume 0.5 $ETH of early-exit trading and network fees, with no additional price impact.

If the market’s required yield rises, a price of **0.94 $ETH per PT** implies approximately **13.17% annualized** over the remaining half-year. Selling 100 PT produces 94 $ETH before exit costs, or **93.5 $ETH net—a 1.7 $ETH loss** against total outlay.

If the required yield falls, a price of **0.99 $ETH per PT** implies approximately **2.03% annualized**. The sale produces 99 $ETH before exit costs, or **98.5 $ETH net—a 3.3 $ETH gain**. Those annualized yields describe the remaining maturity return at the new prices, not the original holder’s realized return.

At the same remaining term, a higher required yield means a lower PT price, and vice versa. But time also matters: a shorter wait for redemption supports a higher price at an unchanged yield. Rising yields therefore do not automatically mean a loss relative to the original purchase.

An actual early exit also depends on liquidity. A thin pool or a large sale can worsen execution through price impact or slippage. Pendle charges swap fees; their calculation scales with time to maturity. Its documentation says redemption after maturity has no protocol fee, although network gas still applies. Neither a displayed annualized yield nor a reference price alone establishes net sale proceeds.

Fixed Units Are Not a Dollar Guarantee

An $ETH-denominated gain can still be a dollar loss if $ETH falls. The underlying token also carries its own risks: Pendle warns that a decline in an interest-bearing token’s exchange rate below its recorded high-water mark can reduce PT’s maturity redemption below the normal accounting-unit amount.

Contract risk sits alongside asset risk. Sky discloses Pendle protocol risk separate from sUSDS, and Pendle warns of risks in third-party contracts. Holding to maturity removes the need to sell at an interim market price; it does not remove those risks. After maturity, PT remains redeemable but earns no further yield for its holder.