Introducing Extended Public Key (XPub) Support

As of today, Pocket allows you to share your xpub, i.e. all Bitcoin addresses from your wallet, in addition to a single Bitcoin address. This way, you will always get your bitcoin paid out to a new, unused Bitcoin address.

By doing so, you follow common practice and reveal less information about your wallet and behavior to the Bitcoin network.

Start with a new order

To use the new function, simply create a new order on pocketbitcoin.com. Select the wallet on which you want to receive your bitcoin and let Pocket determine a Bitcoin address from it.

If you would confirm this Bitcoin address now and finish submitting the order, Pocket would pay out your purchased bitcoin to this one Bitcoin address every time.

Although reusing a Bitcoin address seems to make sense at first glance, it is disadvantageous in the Bitcoin network. This is because all transactions are publicly visible in the Bitcoin network. Different transactions sent to the same Bitcoin address can be clearly linked. This is much harder if a new Bitcoin address is used each time one receives bitcoin.

Xpub to the rescue

The concept of the xpub was introduced by Bitcoin developers in 2012. Xpub stands for Extended Public Key and is an extended variant of the usual public key of a single Bitcoin address. This means that a nearly endless number of Bitcoin addresses can be derived with just one xpub.

The same xpub can always be used to recover the same Bitcoin addresses. Thus, only a single piece of information needs to be held in order to get full read-access to a wallet.

Share your xpub with Pocket

After you have confirmed one of your Bitcoin addresses with Pocket, you can now enrich it with your xpub.

Now you need to find the xpub in your wallet. Wallets display it in different places. Oftentimes you can find the xpub in the settings of a particular wallet account.

BitBoxApp

1. Open your account
2. Click Account info (top right)
3. Copy the value from Extended public key

Ledger Live

1. Open Accounts in the menu
2. Choose your account
3. Click Edit Account (top right)
4. Extend Advanced
5. Copy the value starting with «zpub...»

Trezor Suite

1. Open Accounts at the top
2. Choose your account
3. Open Account at the top
4. Click Show public key
5. Copy the displayed value

BlueWallet

1. Choose your BlueWallet
2. Click ⋯ (top right)
3. Click Show Wallet XPUB
4. Copy the displayed value

Once entered and confirmed, you will have shared all Bitcoin addresses from your wallet with Pocket. Pocket then uses these for your purchases.

If you complete the order now, Pocket will execute each payout to a new Bitcoin address. From now on, individual transactions can no no longer be easily associated with your wallet and you enjoy better privacy in the Bitcoin network.

Pocket requests an empty wallet

We care about your privacy. That's why Pocket only allows xpubs from wallets you haven't used before. This ensures that you don't unintentionally reveal the entire transaction history of a wallet you've been using for a while.

Therefore, create a new account only to be used with Pocket and share this new xpub with us. This way, you will only give Pocket the Bitcoin addresses that you would have used for buying Bitcoin with Pocket anyway. Only send bitcoin from this account and do not use it for any other purpose.

Try it out

We hope you like this new feature and make use of it. Let us know if you have any open questions about the setup. There are many more interesting things to learn about xpub, which we will cover in a separate article soon.

Until then, happy #stackingsats! 🎁