The Maze: Google plans to change how advertisers upload customer records through Data Manager, its advertising-data connection tool, from November 16, 2026. A notice to existing users says encryption will become the default and pre-upload hashing will no longer be required. The practical migration instructions remain the missing piece.
Source: Google. Google’s September 2024 illustration of confidential matching. It explains the existing architecture, not the forthcoming November upload interface.
The Details:
Two different protections. Hashing turns an email address or telephone number into a repeatable, one-way code that can be compared with another code. Encryption locks information so authorized software can unlock it. Today, Google’s formatting instructions tell developers to standardize contact details before hashing them. Email addresses must be lowercase and free of unwanted spaces; telephone numbers need their country codes. These preparation steps make differently written versions of the same contact comparable. A privacy feature does not remove the need to get the underlying records right.
Google would do more preparation. The reproduced notice covers imports for Customer Match, which builds advertising audiences from customer lists, and enhanced conversions, which help connect customer actions to ads. It names customer-record connections, cloud storage, direct file uploads and automated software connections. Google says encrypted records will be unlocked, standardized and matched against Google account information inside an isolated computing environment. It claims this will reduce formatting errors and improve matching accuracy. The notice supplies no measured gain, country list or explanation of what happens to existing uploads that already contain hashes.
The protected room already exists. Google introduced confidential matching in September 2024. It made that protected processing the default for Customer Match data connections, including Data Manager, without extra cost or advertiser action. The new notice therefore changes the preparation and encryption default around an existing system. Crucially, Google’s current encryption guide, updated October 14, still instructs developers to format and hash before encrypting. That guide is not yet an instruction to remove hashing from a working integration.
MarketMaze Take: The useful distinction is between a future processing default and a usable migration plan. Google is proposing to absorb more of the work that makes customer records match. Advertisers still need to know exactly what their existing connection must send before changing it.
A simpler upload can move the trust decision. Google already offers isolated processing; its 2024 announcement also describes proof that specified software ran, called attestation. The relevant question is how records are prepared and protected along the whole route. Calling the new default “encrypted” does not, by itself, establish a new privacy guarantee or prove that more advertising spend will produce sales.
The documentation gap travels across borders. For any advertiser using these connections, the immediate issue is whether a scheduled customer-data upload will keep working. No country expansion is established here. Google may update its instructions before November 16; the mismatch does not prove a faulty rollout. It does mean the notice alone cannot tell an advertiser which preparation step to remove, or promise a better match rate.
Sources: PPC Land, Google Developers, Google Developers, Google
