user70069: Is Blockchain an open source technology or is it owned by a company?
I didn't see it spelled out but Blockchain.com website appears to belong to a company.
There also seems to be different implementations of blockchain databases/ledgers.

user50659: Blockchain is some concept. There are different implementations of blockchain. Most of them open source. The most notable one is the cryptocurrency Bitcoin with their reference implementation -Bitcoin Core.
Blockchain.com is just the company with the website which provides some services related to the bitcoin cryptocurrency and owns very attractive web address.

70069: <p>Is Blockchain an open source technology or is it owned by a company?</p>

<p>I didn't see it spelled out but Blockchain.com website appears to belong to a company.</p>

<p>There also seems to be different implementations of blockchain databases/ledgers.</p>
 50659: <p>Blockchain is some concept. There are different implementations of blockchain. Most of them open source. The most notable one is the cryptocurrency Bitcoin with their reference implementation -<a href="https://github.com/bitcoin/bitcoin" rel="nofollow noreferrer">Bitcoin Core</a>.</p>

<p><a href="https://blockchain.com/" rel="nofollow noreferrer">Blockchain.com</a> is just the company with the website which provides some services related to the bitcoin cryptocurrency and owns very attractive web address.</p>
