# ANNEX S - TRANSACTION PRICE BANDS & NOSTR KEY-ALIGNMENT MATRIX

> Balanced Exchange Framework (BEF) - Framework Version 1.0, 2026-08-22.
> Source of record: https://balancedexchangeframe.work/doc/annex-s

Framework 1.0 retains the three transaction-price bands introduced in 0.23: LOW PRICE below 0,01 EUR; MID PRICE from 0,01 EUR through 0,30 EUR inclusive; HIGH PRICE above 0,30 EUR. A price band describes the economics of a standard native transfer and does not by itself make a coin uninteresting or exclude it from BEF. Dynamic or insufficiently evidenced networks remain LIVE PRICE GATE until CP-58 evidence is available.

The Nostr key-alignment test from 0.22 remains unchanged. Nostr NIP-01 requires secp256k1 Schnorr signatures. A native blockchain key is direct-key aligned only where the wallet/account can use secp256k1 key material and an auditable BIP-340-compatible signing path. Ed25519, sr25519, BLS, shielded-only or principal-only models are not directly Nostr-compatible and require a separate Nostr-link proof or adapter.

Operational safety note: direct technical compatibility is not a recommendation to expose a value-bearing blockchain private key to ordinary Nostr clients. Production use should prefer a dedicated derived/signing key or a proof-of-control link between the blockchain wallet and the Nostr identity.

### 1.0 Practical Classification (fee basis retained from 0.23)

| Coin | Transaction price band | Nostr key-alignment gate | 1.0 BEF result |
| --- | --- | --- | --- |
| LANA | LOW PRICE | NOSTR OK: secp256k1/BIP340 path | REFERENCE / INTERESTING |
| BTC | MID PRICE | NOSTR OK: secp256k1 | INTERESTING - MID PRICE |
| ETH | HIGH PRICE | NOSTR OK: EVM secp256k1 | HIGH PRICE - NOT AUTO-EXCLUDED |
| BNB | LOW PRICE | NOSTR OK: EVM secp256k1 | REMAINS INTERESTING |
| XRP | LOW PRICE | COND: secp256k1 XRPL only; Ed25519 no | CONDITIONAL |
| SOL | LOW PRICE | NOSTR NO: Ed25519 | NOSTR INCOMPATIBLE |
| TRX | LOW with resources / MID fallback | NOSTR OK: secp256k1 | INTERESTING - RESOURCE-CONDITIONAL |
| HYPE | LIVE PRICE GATE | COND: EVM signer evidence needed | LIVE GATE |
| DOGE | LOW PRICE | NOSTR OK: secp256k1 | REMAINS INTERESTING |
| ZEC | MID PRICE + HOLD | PARTIAL/HOLD: transparent only | P24 HOLD - PRIVACY/PROVENANCE |
| XMR | LIVE PRICE GATE + HOLD | NOSTR NO: non-secp model | LIVE GATE/HOLD |
| ADA | MID PRICE | NOSTR NO: Ed25519/BIP32-Ed25519 | NOSTR INCOMPATIBLE - MID PRICE |
| XLM | LOW PRICE | NOSTR NO: Ed25519 | NOSTR INCOMPATIBLE |
| BCH | LOW PRICE | NOSTR OK: secp256k1 | REMAINS INTERESTING |
| GRAM | LOW-MID PRICE | NOSTR NO: TON Ed25519 | NOSTR INCOMPATIBLE - LOW/MID PRICE |
| LTC | LOW PRICE | NOSTR OK: secp256k1 | REMAINS INTERESTING |
| HBAR | LOW PRICE | COND: ECDSA secp256k1 only | CONDITIONAL |
| AVAX | LOW PRICE | NOSTR OK: secp256k1 C-Chain | REMAINS INTERESTING |
| SUI | LOW PRICE | COND: Secp256k1 Sui only | CONDITIONAL |
| NEAR | LOW PRICE / LIVE | COND: secp256k1 access key only | CONDITIONAL |
| TAO | LIVE PRICE GATE | NOSTR NO: sr25519/ed25519 | LIVE GATE |
| DOT | LIVE PRICE GATE | COND: ECDSA only; default sr25519 no | LIVE GATE |
| ICP | LOW PRICE / RESEARCH | NOSTR NO: principal model | NOSTR INCOMPATIBLE |
| ETC | LIVE PRICE GATE | NOSTR OK: EVM secp256k1 | LIVE GATE |
| ATOM | LOW PRICE / LIVE | NOSTR OK: Cosmos secp256k1 | REMAINS INTERESTING |
| ALGO | LOW PRICE | NOSTR NO: Ed25519 | NOSTR INCOMPATIBLE |
| KAS | LOW PRICE | NOSTR OK: secp256k1/Schnorr; verify BIP340 | REMAINS INTERESTING |
| FIL | LIVE PRICE GATE | COND: Filecoin secp256k1 only; BLS no | LIVE GATE |
| APT | LIVE PRICE GATE | COND: Secp256k1 auth only; Ed25519 no | LIVE GATE |
| XTZ | LIVE PRICE GATE | COND: tz2/Secp256k1 only | LIVE GATE |

The fee and Nostr filters are now read independently. The following examples show the corrected interpretation, always subject to COIN x PRODUCT x JURISDICTION and the other P24 gates:

- LANA - reference implementation; LOW PRICE reference; native BEF anchor.

- BTC - MID PRICE on the stated ~EUR 0.078 simple-transfer reference; Nostr-compatible secp256k1 key model; no longer excluded merely because the fee exceeds one cent.

- ETH - HIGH PRICE on the stated ~EUR 0.354 transfer example; Nostr-compatible EVM/secp256k1 key model; high transaction cost is an economic-use signal, not an automatic BEF exclusion.

- BNB, XRP, DOGE, BCH, LTC, HBAR, AVAX C-Chain, ATOM and KAS - LOW PRICE on the stated references; Nostr alignment remains as specified in the matrix.

- TRX - LOW PRICE when sufficient bandwidth/resources are available; MID PRICE on the stated unstaked fallback; Nostr-compatible secp256k1 key material.

- ZEC - MID PRICE on the stated fee reference, but P24 HOLD remains for privacy/provenance design; fee alone is not the exclusion reason.

- ADA - MID PRICE on the stated fee reference, but ordinary wallet keys remain Nostr-incompatible under the current key-alignment test.

- GRAM / TON - the stated reference spans LOW to MID PRICE, but the ordinary TON Ed25519 wallet model remains Nostr-incompatible.

- SUI, NEAR, ICP and ALGO have LOW PRICE references where measured, while their separate Nostr/account-model constraints remain unchanged; HYPE, XMR, TAO, DOT, ETC, FIL, APT and XTZ remain LIVE PRICE GATE where current representative fee evidence is not closed.

### 1.0 Key Interpretation Rules

- LOW PRICE (< EUR 0.01) is the preferred cost profile for frequent micro/retail circulation, but it does not override Nostr or other P24 gates.

- MID PRICE (EUR 0.01-EUR 0.30 inclusive) remains potentially usable in BEF; suitability depends on transaction size, frequency and the complete technical/regulatory profile.

- HIGH PRICE (> EUR 0.30) is less attractive for frequent small transfers, but the coin is not automatically excluded from BEF and may remain suitable for larger-value or lower-frequency flows.