Should advisors give Claude Cowork access to client files?
By Dr. Leigh Coney, Founder of WorkWise Solutions · Updated October 20, 2026
Short answer: Not broad access, and Anthropic says the same. Its Cowork safety guide tells users to avoid granting access to local files with sensitive information, like financial documents. Cowork can read and write files in the folders you share and, with your permission, delete them, and in a cloud session the files it opens are processed on Anthropic's servers. For client work, give Cowork a dedicated folder holding only what the task needs, prefer read-only connectors to your systems of record, keep manual approval on, and keep it away from signed-in browser sessions.
Anthropic is unusually direct here. Its Cowork safety guide lists, among its precautions: "Avoid granting access to local files with sensitive information, like financial documents." For an advisor, that describes most of the hard drive.
The reason is what Cowork can do. It can read and write files in any folder you share, and permanently delete them once you approve. If your firm runs Cowork sessions in the cloud, Anthropic notes that local files it opens are processed on Anthropic's servers rather than staying on your computer. On a managed computer, connecting local folders also makes them reachable from a cloud session.
Then there is prompt injection. A client statement, an email or a web page can carry hidden instructions. Anthropic explains when that becomes dangerous: "two things must be true at the same time: Claude can read information outside your trusted boundary, and can perform actions that could compromise the user." An advisor's laptop often has both. Anthropic says the chance of an attack is "still non-zero."
History is the third issue. For local sessions, Cowork keeps conversation history on the advisor's computer, outside Anthropic's retention policies, and admins can't delete it centrally. A lost laptop is now also a lost set of client conversations.
Cowork can still do useful client work. Keep the access narrow:
- A dedicated working folder. Anthropic suggests one. Put in only the documents the task needs, and clear it when the task is done.
- Connectors before files. A read-only connector to Orion or Wealthbox returns what a skill asks for. A shared folder exposes everything in it.
- Manual approval. Anthropic says to switch to Manually approve when a task touches sensitive files, accounts or sites.
- No signed-in browsing. On the built-in browser and Claude in Chrome, Anthropic writes: "we strongly advise against using either to manage or take actions involving sensitive information."
- Encrypted, managed laptops. Local history lives there, so device controls are now client-data controls.
Write the rule into your AI policy in one sentence: client documents reach Claude through approved connectors or a task folder, never through a shared drive.
I set it up for RIAs. Through WorkWise Solutions, the Claude for Financial Advisors setup covers the plan decision, the connectors, your firm's rules in the skills and archive capture, at a fixed price: $10,000 for firms of 1 to 10 people or $20,000 for 11 to 25, in two to four weeks.