Client books, client mail, your machine.
Klar filters spam inside Apple Mail, on your own Mac. The extension that reads your inbox has no network permission, so classification sends no client material to a vendor.
Confidentiality is a principle, not a setting.
Confidentiality is one of the five fundamental principles of the ICAEW Code of Ethics: you respect the confidentiality of information acquired through professional and business relationships, and you do not disclose it without the client's authority. The Code then goes further than the headline. It asks you to take reasonable steps to ensure that the people whose assistance you rely on respect that duty too.
A practice inbox is a stream of exactly the material the principle is about: statements, valuations, a client's plans before they are public, and the one message in March that explains why the numbers moved. Putting a filter in front of it is not forbidden. It is a decision you carry, including for the provider behind it.
ICAEW Code of Ethics: the fundamental principlesNo third party in the filtering path.
Klar is a Mail extension. It scores each message on your Mac as it arrives without uploading it. There is no third party in the filtering path, so no filtering processor holds a copy of your client's year.
The part of Klar that reads your mail is an Apple-sandboxed Mail extension shipped without the network entitlement. It is not that we promise not to send your mail anywhere. It is that macOS refuses the connection, because the permission was never requested. Classification happens on your Mac, instantly.
What that means in practice
- No network access
- The free App Store app and its Mail extension ship without the network entitlement. macOS refuses any connection they try to open. This is a permission the app does not hold, not a policy it promises to follow.
- The model ships with the app
- The classifier is a multilingual transformer inside the app bundle. Nothing is fetched when a message arrives, so it works the same on a train as it does in the office.
- No account
- There is nothing to sign up for and no licence server the free app calls. Unless you contact us or choose to send an Email report, we do not know who you are.
- The engine is open source
- The scoring engine is AGPLv3. Your IT people do not have to take our word for any of this. They can read it, build it, and watch what it does.
Questions your compliance officer will ask
Will it slow Mail down when we are busy?
Classification is instant, on your Mac as mail arrives. You are not waiting on a round trip to anyone's server, which is the part that usually makes filtering feel slow.
Our clients send us documents. Does any of that reach you?
Not for filtering. The free App Store app and its Mail extension have no network permission. Klar reads the subject and the start of the body entirely on your Mac. The separate Email report action opens an editable draft in your mail app, so do not send a report containing client material unless you are authorised to share it.
Does filtering send anything off the machine?
No. The free App Store app and its Mail extension have no network permission. If you choose Email report, Klar opens an editable draft in your own mail app; nothing leaves until you send it. Do not include confidential correspondence unless you are authorised to share it. Klar Plus, the paid companion you install yourself, separately uses the network for its licence, model and version checks. None carries your mail. The full list is on the local-first page.
Do we need a data processing agreement with you?
That is a question for your own counsel, and it depends on which part of Klar you run. Routine filtering sends us nothing. A user who sends an Email report may share selected messages, diagnostics and a removable monthly usage summary; our privacy policy explains what we then hold. Decide whether staff may use that report action with confidential correspondence.
What we are not claiming.
We are not offering legal advice, and a spam filter does not make anyone compliant. Your obligations are yours, and your bar, your regulator or your DPO is the right place to test them. What we can tell you is exactly where the software runs and what it is permitted to do, which is the part most vendors leave you to infer.
We are also not claiming perfect filtering. No filter is, and any vendor quoting you a single accuracy number is quoting a number from their corpus, not your inbox. What we will say is that being wrong about a message on your Mac and being wrong about it on someone else's server are not the same kind of wrong.
Read the whole local-first argumentTry it on the inbox you cannot risk.
macOS 14 or later, Apple Silicon. No account, no cloud classification, no setup. It filters inside Apple Mail on your Mac.
