<p>That is not correct!</p>
<p><a href="https://github.com/input-output-hk/cardano-ledger-specs" rel="nofollow noreferrer">The ledger specifications</a> are licensed under Apache License 2.0 and <a href="https://eprint.iacr.org/2017/573.pdf" rel="nofollow noreferrer">the paper</a> is also open to public.</p>

CC BY-SA 4.0
2021-06-01T02:07:58.067Z
To be fair, the source states "The Cardano blockchain uses the proprietary Ouroboros Praos protocol to facilitate consensus on the chain."
Matthias Sieber
CC BY-SA 4.0
2021-06-01T06:23:36.330Z
Yes, the source is wrong. Or probably the wording is wrong.
Marek Mahut - StakeNuts
CC BY-SA 4.0
2021-06-01T09:38:03.357Z
I've created an issue [here](https://github.com/cardano-foundation/stake-pool-school-handbook/pull/46) to get the source corrected
isedwards
CC BY-SA 4.0
2021-06-01T12:37:45.820Z
And the CF merged it right away! CF rocks.
Marek Mahut - StakeNuts
CC BY-SA 4.0
2021-05-30T19:42:08.477Z
2021-05-30T19:42:08.477Z
Marek Mahut - StakeNuts
<p>The <a href="https://cardano-foundation.gitbook.io/stake-pool-course/lessons/introduction/about-cardano#slots-and-epochs" rel="noreferrer">slots and epochs</a> section of the Cardano Stake Pool Course states that the Ouroboros <a href="https://iohk.io/en/research/library/papers/ouroboros-praosan-adaptively-securesemi-synchronous-proof-of-stake-protocol/" rel="noreferrer">Praos protocol</a> is proprietary.</p>
<p>Is this correct and, if so, is there a reason why this central part of the implementation needs to be proprietary?</p>

CC BY-SA 4.0
2021-06-01T09:49:58.020Z
Great catch! I have no idea how the word "proprietary" found its way in there. It's wrong, of course. I've just merged your pull request. BTW we moved this old course to the new developer portal that is being built. A lot of things are already improved, but if someone wants to contribute to the SPO category, please get in touch with me.
adatainment
CC BY-SA 4.0
2021-06-01T13:24:01.053Z
@adatainment I'd be interested in contributing.  Also - it would be good to see whether Chris Moreton's [fork of plutus-pioneer-program](https://github.com/chris-moreton/plutus-pioneer-program) can be merged, he is doing a great job of documenting the lectures: https://plutus-pioneer-program.readthedocs.io/en/latest/
isedwards
<ouroboros>
Is the Ouroboros Praos protocol proprietary?
# Is the Ouroboros Praos protocol proprietary?

(Asked by: username_0 on 2021-05-30)

The [slots and epochs](https://cardano-foundation.gitbook.io/stake-pool-course/lessons/introduction/about-cardano#slots-and-epochs) section of the Cardano Stake Pool Course states that the Ouroboros [Praos protocol](https://iohk.io/en/research/library/papers/ouroboros-praosan-adaptively-securesemi-synchronous-proof-of-stake-protocol/) is proprietary.

Is this correct and, if so, is there a reason why this central part of the implementation needs to be proprietary?

**Tags:** ouroboros
> **Comments:**
> **username_1**: Great catch! I have no idea how the word "proprietary" found its way in there. It's wrong, of course. I've just merged your pull request. BTW we moved this old course to the new developer portal that is being built. A lot of things are already improved, but if someone wants to contribute to the SPO category, please get in touch with me.  
> **username_0**: @adatainment I'd be interested in contributing.  Also - it would be good to see whether Chris Moreton's [fork of plutus-pioneer-program](https://github.com/chris-moreton/plutus-pioneer-program) can be merged, he is doing a great job of documenting the lectures: https://plutus-pioneer-program.readthedocs.io/en/latest/  

---

## 1 answers

### Answer by username_2 on 2021-05-30. Score: 2 | Accepted answer

That is not correct!

[The ledger specifications](https://github.com/input-output-hk/cardano-ledger-specs) are licensed under Apache License 2.0 and [the paper](https://eprint.iacr.org/2017/573.pdf) is also open to public.

> **Comments:**
> **username_3**: To be fair, the source states "The Cardano blockchain uses the proprietary Ouroboros Praos protocol to facilitate consensus on the chain."  
> **username_2**: Yes, the source is wrong. Or probably the wording is wrong.  
> **username_0**: I've created an issue [here](https://github.com/cardano-foundation/stake-pool-school-handbook/pull/46) to get the source corrected  
> **username_2**: And the CF merged it right away! CF rocks.  

---

