<p>The last block that did not have BIP91 rules active was the one with height 477119, with hash <a href="https://blockchain.info/block-index/1605960" rel="nofollow noreferrer">00000000000000000022552c92fdc5ac6c31a95f54d9ed9fcdf0fe00ff134773</a>.</p>

<p>BIP91 uses BIP9, but with modified period sizes and threshold. It uses windows of 336 blocks, and requires 269 blocks to signal on bit 4. The window that ranged from block 476448 to 476783 (inclusive) had 284 blocks that signalled on bit 4. As a result, BIP91 locked in, and the next window of 336 blocks, ranging from 476784 to 477119 (inclusive) was spent in the locked in state. As of block 477120, BIP91 transitioned to the active state, and nodes that implement BIP91 will require signalling for bit 1 as of that block.</p>

CC BY-SA 3.0
2017-07-23T05:15:52.510Z
Thanks... is there a reference for this assertion?
Tom Hale
CC BY-SA 3.0
2017-07-23T06:13:23.120Z
I provided some more background.
Pieter Wuille
CC BY-SA 3.0
2017-07-23T06:38:46.170Z
Thank you, but where are you sourcing this data from?
Tom Hale
CC BY-SA 3.0
2017-07-23T06:39:01.700Z
The blockchain.
Pieter Wuille
CC BY-SA 3.0
2017-07-23T05:02:06.523Z
2017-07-23T06:02:05.413Z
2017-07-23T06:02:05.413Z
Pieter Wuille
<p><a href="https://www.xbt.eu/" rel="nofollow noreferrer">https://www.xbt.eu/</a> says:</p>

<blockquote>
  <p>BIP91 ACTIVATED!</p>
  
  <p>Non-SegWit signaling blocks will be orphaned.</p>
</blockquote>

<p>What was the last block before BIP91 activated?</p>

<segregated-witness><bip91>
What was the last block before BIP91 activated?
Tom Hale
# What was the last block before BIP91 activated?

(Asked by: username_0 on 2017-07-23)

<https://www.xbt.eu/> says:

> BIP91 ACTIVATED!
>
> Non-SegWit signaling blocks will be orphaned.

What was the last block before BIP91 activated?

**Tags:** segregated-witness, bip91


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## 1 answers

### Answer by username_1 on 2017-07-23. Score: 2 | Accepted answer

The last block that did not have BIP91 rules active was the one with height 477119, with hash [00000000000000000022552c92fdc5ac6c31a95f54d9ed9fcdf0fe00ff134773](https://blockchain.info/block-index/1605960).

BIP91 uses BIP9, but with modified period sizes and threshold. It uses windows of 336 blocks, and requires 269 blocks to signal on bit 4. The window that ranged from block 476448 to 476783 (inclusive) had 284 blocks that signalled on bit 4. As a result, BIP91 locked in, and the next window of 336 blocks, ranging from 476784 to 477119 (inclusive) was spent in the locked in state. As of block 477120, BIP91 transitioned to the active state, and nodes that implement BIP91 will require signalling for bit 1 as of that block.

> **Comments:**
> **username_0**: Thanks... is there a reference for this assertion?  
> **username_1**: I provided some more background.  
> **username_0**: Thank you, but where are you sourcing this data from?  
> **username_1**: The blockchain.  

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