diff --git a/specs/main.md b/specs/main.md
index ce70c47e..7f2a8c35 100644
--- a/specs/main.md
+++ b/specs/main.md
@@ -125,7 +125,7 @@ A call frame consists of the following, word-aligned:
 |       |                      |                   | **Unwritable area begins.**                                                   |
 | 8     | `uint32`             | out offset        | Offset from start of this call frame to out count, in bytes.                  |
 | 32    | `byte[32]`           | to                | Contract ID for this call.                                                    |
-| 8*64  | `byte[8][64]`        | regs              | Saved registers from previous  context.                                       |
+| 8*64  | `byte[8][64]`        | regs              | Saved registers from previous context.                                        |
 | 8     | `uint8`              | in count          | Number of input values.                                                       |
 | 8     | `uint8`              | out count         | Number of return values.                                                      |
 | 8     | `uint16`             | code size         | Code size in bytes (not padded to word alignment).                            |
diff --git a/specs/opcodes.md b/specs/opcodes.md
index 9ef44283..1edb158d 100644
--- a/specs/opcodes.md
+++ b/specs/opcodes.md
@@ -460,7 +460,7 @@ Otherwise, `$of` and `$err` are cleared.
 | Encoding    | `0x00 rd rs rt -`                                           |
 | Notes       |                                                             |
 
-If `$rt > tx.input[$rs].maturity`, halt, returning `false`. If the input `$rs` is not of type [`InputType.Coin`](./tx_format.md), halt, returning `false`.
+If `$rt > tx.input[$rs].maturity` or if the input `$rs` is not of type [`InputType.Coin`](./tx_format.md), verification failed and operation depends on the context type. In a predicate context, [return](#return-return-from-context) `false`. In other contexts, [revert](#revert-revert).
 
 Otherwise, advance the program counter `$pc` by `4`.
 
@@ -476,7 +476,7 @@ See also: [BIP-112](https://github.com/bitcoin/bips/blob/master/bip-0112.mediawi
 | Encoding    | `0x00 rd rs - -`                                 |
 | Notes       |                                                  |
 
-If `$rs > tx.maturity`, halt, returning `false`.
+If `$rs > tx.maturity`, verification failed and operation depends on the context type. In a predicate context, [return](#return-return-from-context) `false`. In other contexts, [revert](#revert-revert).
 
 Otherwise, advance the program counter `$pc` by `4`.