I recently read Zack Shapiro’s incredible breakdown of the “Claude-Native Law Firm.” If you haven’t read it yet, go do that now! It is a masterclass in how legal professionals should be thinking about AI—using “Skills” to encode legal judgment and “Cowork” to turn the AI into a substantive partner.

But while Zack gives us the acceleration, we need to talk about the brakes.

There is a massive governance gap in his advice that, if followed blindly by attorneys, could land you in hot water. Zack mentions using ZDR (Zero Data Retention) on the API side, but he also leans heavily on “Cowork” (the Claude.ai web interface).

Here is the legal malpractice issue that is waiting to happen: ZDR does not cover Claude Cowork. Claude Cowork retains your privileged information.

If you are a small or mid-size firm running out to download the Claude Desktop App because you read Zak’s post, you are walking into a compliance minefield. You cannot get the protections you need to maintain attorney-client confidentiality (ZDR) on the plan you can afford.

Here is the breakdown of why you are hitting this wall—and how firms your size actually solve it.

1. The “ZDR vs. Cowork” Conflict

How do we bridge the gap between the API (which allows ZDR) and “Cowork” (the Projects/Web UI)?

The hard truth? You can’t. At least not as a small firm.

• With API (Stateless): You send data, the model answers, and the data is wiped immediately. The model has no memory of who you are or what you said five minutes ago. This is perfect for Zero Data Retention.

• Cowork/Web UI (Stateful): The entire point of the Cowork interface is persistence. It needs to save your chat history, your uploaded documents, and your project context so you can log back in tomorrow. If they applied ZDR to the web interface, your chats would vanish the moment you closed the tab.

How firms handle this split: If you cannot get a ZDR agreement for the web interface (which is standard), you generally have two workflows:

• The “Air Gap” Method: You strictly prohibit putting Privileged/PII data into the web interface. You only process that data through a custom tool you build (or buy) that runs on the API where ZDR is active. This is difficult because then you can’t have things like contracts uploaded and reviewed by Cowork unless you have the Enterprise plan.

• The “Trust but Verify” Method: You use Claude’s Team Plan (not Enterprise). This allows you to opt out of model training. Claude still retains data for a short window (usually 30 days) for abuse monitoring, but they contractually agree not to train on it. I don’t think this method is sufficient to overcome attorney-client privilege concerns—especially not after the recent ruling on the use of AI in United States v. Heppner. See United States v. Heppner, no. 25-cr-503, 2026 U.S. Dist. LEXIS 32697, 2026 WL 436479 (S.D.N.Y. Feb. 17, 2026).

2. How to get Compliance/ZDR as a Small Firm

You might be thinking, “Fine, I’ll just sign the ZDR contract for the API.”

Not so fast.

You likely cannot get a direct ZDR/BAA contract with Anthropic as a small firm. Like OpenAI, Anthropic generally gates these custom compliance agreements behind their Enterprise tier, which often requires a minimum of 20+ seats or a high annual spend (e.g., $30k+). They simply do not have the legal support staff to redline contracts for every two-lawyer partnership.

The Solution: Use a “Reseller” Cloud Provider

You don’t need to sign a contract with Anthropic to use Claude with full compliance. You can use AWS Bedrock (Amazon) or Google Vertex AI. Both Amazon and Google host the Claude models. When you access Claude through them, the game changes:

• Compliance: You fall under Amazon or Google’s enterprise terms, not Anthropic’s consumer terms. Both AWS and Google offer BAAs and Zero Data Retention policies that are accessible to a single developer or a 2-person firm immediately.
• No Minimums: You pay for what you use. There is no 20 or 50-seat minimum.
• Security: Your data stays within your AWS/Google cloud environment. Anthropic never sees your data; the model runs inside the cloud provider’s secure perimeter.

Governance first. Cool features second.

Need help setting up a compliant “Bring Your Own Key” environment for your firm? Drop a comment below or DM me.

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Disclaimer: This article is for informational purposes only and does not constitute legal advice or create an attorney-client relationship. Every firm has unique compliance requirements; please consult your own counsel or compliance officer regarding specific data privacy obligations.