Per Maple AI, kimi k2.6: "Yes, BIP-110 would constrain certain Taproot scripts, and under specific circumstances it could render some UTXOs unspendable. **How it constrains Taproot scripts** BIP-110 proposes (among other things) to make the following invalid in tapscripts for blocks mined after activation: - **`OP_IF` and `OP_NOTIF`**: These opcodes would be disallowed entirely in tapscript, even in branches that are not executed. - **Large control blocks**: Taproot control blocks larger than 257 bytes would be invalid — this effectively caps the Taptree at 128 script leaves. - **Large data pushes**: Data pushes greater than 256 bytes would be invalid. **Could this make UTXOs unspendable?** Yes, but primarily for a specific edge case. BIP-110 includes a **grandfather clause**: UTXOs created *before* activation are exempt and can still be spent using old scripts. However, this protection does not fully cover: - **Pre-signed or timelocked transactions** created before activation but broadcast *after* activation. - UTXOs that rely **solely** on a now-invalidated script path (e.g., one using `OP_IF`) and have no alternative valid spending path (no key-path spend, no other valid tapleaf). If a Taproot output was constructed to force spending through a script leaf that BIP-110 invalidates, and that transaction is only revealed after activation, the consensus rules would reject the spend. With no valid path remaining, those funds would become unspendable for the duration of the softfork. This has led to criticism that the proposal risks a form of *de facto confiscation* for certain complex Taproot contracts, even though standard pre-activation UTXOs are technically grandfathered."