MarkClient Privacy Policy

Effective date: October 7, 2026

NOT AN OFFICIAL MINECRAFT PRODUCT. NOT APPROVED BY OR ASSOCIATED WITH MOJANG OR MICROSOFT.

MarkClient (the launcher and the in-game client) is made by AdriMark LLC, a Louisiana limited liability company (“we”, “us”). This policy explains what data MarkClient uses, what we keep, what stays on your PC and which other services are involved. Use of MarkClient is also covered by our Terms of Service.

Contact: AdriMark@MarkCraft.org

In short

• We never see your Microsoft password or your card details.
• We do not sell your data or use it for ads.
• Your settings, logs, replays and other files stay on your PC.
• Our server keeps only what MarkClient needs to work: your plan, your Plus purchase record, your Credits choice, your name color (if you set one) and your cosmetics and rewards.
• While you play signed in, MarkClient keeps a live connection to our server for the game server you are on. Your online presence and status are held only in memory and dropped when you disconnect.
• If you buy Plus, you can choose to show your gamertag in the public Credits. It is off unless you turn it on.
• You can ask us to see or delete your data at any time.

Words we use

• MarkClient Plus (“Plus”) is the paid option. It turns on extra features, such as the status display, AFK status and name color.
• Your Microsoft account is the only account involved. There is no separate MarkClient account.

What we get when you sign in to the launcher

You sign in on Microsoft’s own page or through Windows. We never see or store your Microsoft password.

After you sign in, the launcher gets your Xbox gamertag and Xbox user ID (XUID) from Xbox Live. To check your plan, the launcher sends our server a short-lived Xbox Live token. Our server uses it once to ask Xbox who you are. We do not store that token.

Xbox also tells the launcher your account’s age group. The launcher uses it only to stop child accounts from signing in, and does not store it.

What our server stores

• Your plan: Free or Plus, a beta-access flag and when they last changed, saved under your XUID.
• Your Plus purchase and upgrades: for each, the checkout and payment IDs, the amount and currency, whether it was a test purchase, when it happened and whether it was refunded, saved under your XUID. We do not store your real name or email on our server.
• Your Plus license key (older versions of MarkClient only): older versions turned on the status with a license key. We store only a scrambled form of the key (a hash, not the key itself), when it was created, when it was last used and the in-game name linked to it. The current version doesn’t use license keys.
• Your Credits entry (Plus only): your Credits name style (from what you paid for Plus and upgrades), whether you chose to be shown and, only while you are shown, your gamertag. If you stop showing your name, or your payment is fully refunded, we delete the stored gamertag within an hour. We keep your style and your choice so we can show you again if you opt back in.
• Your name color (Plus, only if you set one): saved under your XUID. Other MarkClient users on the same game server can see it in their player list.
• Status sent by older versions of MarkClient: older versions saved your in-game name (in lower case), recording, streaming and AFK on our server; those disappear at most 30 minutes after the last update. The current version doesn’t save them (see “The live connection”).
• Cosmetics and rewards (when you use them): the cosmetics you own and how you got each one, what you have equipped, the codes you redeemed, your referral code and who referred whom, the playtime milestone you reach, only to unlock its reward (we don’t store your playtime), your linked Discord user ID and Discord roles (only if you link Discord) and when we first saw your XUID.

How the status works:

• AFK means Windows saw no keyboard or mouse input on your PC for the AFK time you chose.
• Recording, streaming and AFK are never saved. Our server holds them in memory only while you are connected and drops them the moment you disconnect or leave the world.
• Your name color stays stored until you turn it off or ask us to delete it.

The live connection (all signed-in users, free too)

While the game runs and you are signed in to the launcher, MarkClient keeps one connection open to our server for the game server you are on. It closes when you leave the world, eject MarkClient or close the game. Through it we receive:

• your XUID and gamertag (from the launcher’s sign-in);
• your in-game name as the player list shows it;
• the address of the game server you are on, or for a local world a scrambled code (a hash) made from the world’s name. This is new: before this change, MarkClient never sent us the server address;
• the names of the other players in your player list, so we can tell you which of them are MarkClient users;
• with Plus, your recording, streaming and AFK status and your name color.

Your online presence and status are held only in memory while you are connected, and are dropped when you disconnect. While you are connected, our server also keeps which game server you are on (its address or code) with your XUID, so a cosmetic you equip shows at once; it is deleted when you disconnect. Your name color is stored as described above. We tell you only about other MarkClient users connected for the same game server, and they see only your gamertag (as the name your status shows under), status, AFK, name color, whether you have Plus and the cosmetic you have equipped (its id and picture). We store nothing about players who don’t use MarkClient; their names are only compared in memory. To stop the connection, sign out of the launcher or turn off the Tab List module.

The Credits (Plus buyers)

The Credits in the launcher thank Plus buyers who choose to be shown. The Credits are public: anyone can see them, in the launcher or online. They show:

• the gamertag of each Plus buyer who chose to be shown;
• each name’s style. The style shows roughly what you paid: a gold name means $10 or more, a rainbow name means $20 or more.

Your name is shown only if you choose. Only adult Xbox accounts can choose this. You can tick “Show my gamertag in the public Credits” when you buy Plus, or turn on “Show me in Credits” in the launcher’s Settings later. To stop, turn it off or email us; your name leaves the Credits within an hour. Your choice never affects Plus. Once shown, your gamertag can stay in caches for up to an hour, and people may take screenshots or copies that we can’t delete.

Your IP address

Every request and connection to our server comes with your IP address, as with any website. Our server keeps it briefly in memory to limit how often one address can call it. We do not save it. Cloudflare, which runs our server, also sees it (see below).

What stays on your PC

These are saved on your PC (mostly in %LOCALAPPDATA%\MarkClient) and we do not upload them:

• your settings (config.json), including a Plus license key if you entered one in an older version (a key works for one in-game name, and we can revoke a key that is abused);
• the game’s launch file, which holds the launcher’s 24-hour session token while you are signed in, so MarkClient can open the live connection (the token is never logged);
• logs;
• replays, which also record the other players who were near you;
• video exports and schematics;
• minimap images and waypoints, saved under the world’s name or the server’s address;
• your playtime;
• your cached account details (gamertag, XUID, plan) and skin;
• game files the launcher downloaded, and the backups the launcher makes before it overwrites game data;
• the launcher’s own device identity for Microsoft’s licensing service (device.dpapi, protected by your Windows account), made when you first install a version from the launcher; it holds no account data of yours.

Sign-in tokens: if you sign in through your browser, the launcher keeps a Microsoft refresh token in Windows Credential Manager (protected by your Windows account) so you stay signed in. If you sign in through Windows, no token is stored. We never receive this token.

Signing out in the launcher deletes the stored token, removes Windows’ sign-in permission for MarkClient and deletes the cached account details and skin.

Other services MarkClient uses

• Microsoft and Xbox Live: sign-in, your gamertag, XUID, age group and profile picture, and the game downloads.
• MCCompanion: receives your gamertag, to find your skin.
• GeyserMC: receives your XUID, to find your skin. When we turn on Plus for a gamertag, our server asks GeyserMC for its XUID.
• Mojang (textures.minecraft.net), or the image address MCCompanion returns: sends your skin image.
• Cloudflare: runs our server and sees your IP address, like any web host.
• GitHub: the launcher reads the list of game versions (the GdkLinks project). The first time you export a replay video, MarkClient downloads FFmpeg from GitHub (a fixed BtbN build, checked against a known hash).
• Stripe (Link): sells MarkClient Plus through Stripe Managed Payments. Link, Stripe’s checkout service, is the merchant of record: it handles your payment, sales tax or VAT, receipts, payment support and disputes. When you check out, our server sends Stripe your XUID and gamertag so the purchase can be matched to your account. Through our Stripe account we receive the details you enter at the checkout (your email, name and billing address, which Stripe needs to work out tax), the amount, currency and payment IDs. We never see your full card number or security code. Stripe’s and Link’s own terms and privacy policies apply to the payment.
• Discord: only if you link your Discord account. We use your Discord user ID to add you to the MarkClient Discord server and to give or remove the Plus role. We never see or store your Discord password or login. Discord Rich Presence (on by default, off in Settings) shows that you’re playing MarkClient through the Discord app on your own PC. It sends nothing to us.

The in-game client identifies itself as “MarkClient” when it calls our server. Each of these services has its own privacy policy.

Why we use your data

• To provide MarkClient and Plus (our contract with you): sign-in, your plan, your license key, cosmetics and rewards.
• To keep the service safe and working (our legitimate interests): rate limits, stopping abuse and fixing problems, and the live connection.
• Because you chose it (your consent): the status display, linking Discord and showing your gamertag in the Credits. You can withdraw consent at any time by turning the feature off or emailing us.
• Because the law requires it (legal obligation): payment and tax records.

We do not sell or share your personal information for cross-context behavioral advertising. We do not send you marketing email unless you agree to it.

Do Not Track: MarkClient does not track you across other websites or apps, so it treats every visit the same whether or not your browser sends a Do Not Track signal.

How long we keep it

Everything on our server is kept until you ask us to delete it or we shut the service down. The exceptions: your online presence, recording, streaming and AFK are held only in memory while you are connected, and a status saved by an older version disappears at most 30 minutes after its last update, and your Credits gamertag is deleted within an hour after you stop showing your name or your payment is fully refunded.

Your rights

Depending on where you live, you can ask us to:

• show you the data we have about you (access);
• correct it;
• limit how we use it (restriction);
• delete it;
• give you a copy in a portable format;
• stop using it for a purpose you object to;
• withdraw a consent you gave.

How to ask: email AdriMark@MarkCraft.org with your gamertag. We may ask you to prove the gamertag is yours, for example by signing in to the launcher. We reply within 30 days. You can also complain to your local data protection authority.

Where your data is processed

We are based in the United States. Our server (Cloudflare) and the services above may process your data in the United States and other countries. Where the law requires safeguards for these transfers, we rely on the ones our providers offer, such as the European Commission’s standard contractual clauses.

Security

We keep as little data as we can, store only a hash of license keys and use encrypted (HTTPS) connections to our server. No system is perfectly secure. If a breach affects your data, we will notify you and the authorities as the law requires.

Children

You must be at least 13 to use MarkClient. Xbox accounts that Microsoft marks as child accounts can’t sign in to the launcher. Only adult Xbox accounts can choose to be shown in the Credits. If we learn that we hold data of a child under 13, we delete it. Parents and guardians can email AdriMark@MarkCraft.org to ask what we hold or to have it deleted.

Changes

We may update this policy. We will post the new version in the launcher with a new effective date, and tell you in the launcher before important changes take effect.

Questions: AdriMark@MarkCraft.org