<p>No, bitcoin transactions that stop being valid after a certain point in time are not possible</p>

CC BY-SA 4.0
2019-01-26T12:57:51.387Z
Out of curiosity, are there proposed opcodes such as `OP_PUSHTXDATA` from Johnson Lan which allow for an expiration mechanism? There is no timestamp on the transaction, so specifically `OP_PUSHTXDATA` wouldn't allow to construct an expiration mechanism. Instead, this hypothetical op_code that would enable expiration would need the ability to push the header height to the stack ... anything such proposals so far?
James C.
CC BY-SA 4.0
2019-01-26T08:38:02.333Z
2019-01-26T08:38:02.333Z
meshcollider
<p>Is it possible to give an expiration time to a Bitcoin transaction so that after a definite time, it can no longer be mined? </p>

<transactions><unconfirmed-transactions>
Transaction with expiration time
Bruce Wayne
# Transaction with expiration time

(Asked by: username_0 on 2019-01-26)

Is it possible to give an expiration time to a Bitcoin transaction so that after a definite time, it can no longer be mined?

**Tags:** transactions, unconfirmed-transactions


---

## 1 answers

### Answer by username_1 on 2019-01-26. Score: 4 | Accepted answer

No, bitcoin transactions that stop being valid after a certain point in time are not possible

> **Comments:**
> **username_2**: Out of curiosity, are there proposed opcodes such as `OP_PUSHTXDATA` from Johnson Lan which allow for an expiration mechanism? There is no timestamp on the transaction, so specifically `OP_PUSHTXDATA` wouldn't allow to construct an expiration mechanism. Instead, this hypothetical op_code that would enable expiration would need the ability to push the header height to the stack ... anything such proposals so far?  

---

