Re: [Secdispatch] CCPA Do-Not-Sell

Benjamin Kaduk <> Fri, 27 March 2020 19:28 UTC

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Date: Fri, 27 Mar 2020 12:28:12 -0700
From: Benjamin Kaduk <>
To: Sebastian Zimmeck <>
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Subject: Re: [Secdispatch] CCPA Do-Not-Sell
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On Sat, Mar 21, 2020 at 08:08:40PM -0400, Sebastian Zimmeck wrote:
> At the beginning of this year the California Consumer Privacy Act (CCPA)
> became effective. In addition to the rights of data access and deletion,
> this new privacy law gives consumers the right to opt out from the sale of
> personal information. A "sale" is understood broadly and likely covers, for
> example, a website or app disclosing location data or device identifiers to
> an ad network for purposes of monetization. Now, the most recent regulations
> to the CCPA
> <>
> published
> by the California Attorney General specify that automatic signals
> communicating a user's decision to opt out must be respected. Here is the
> relevant language:
> "If a business collects personal information from consumers online, the
> business shall treat user-enabled global privacy controls, such as a
> browser plugin or privacy setting, device setting, or other mechanism, that
> communicate or signal the consumer’s choice to opt-out of the sale of their
> personal information as a valid request ... ."
> I am interested in setting up a working group on such device controls. The
> Do-Not-Sell signal could be similar to a Do-Not-Track (DNT) signal.
> However, the difference is that recipients of the DNT signal were not
> required to comply with the signal. Rather, they only needed to *say*
> whether they would comply; per the California Online Privacy Protection Act
> (CalOPPA).
> Also, the CCPA may have substantial impact beyond California as some
> companies, e.g., Microsoft, already made clear that they would apply the
> CCPA to all consumers in the US.
> It would be great to get a discussion started ...

It's not really clear to me how much discussion is needed...
if one assumes that you're just considering a HTTP header field, then the
only technical question I can think of is whether there's intended to be
some level of richness of expressivity vs. a boolean signal "don't sell my
data".  At that point it is mostly a matter of writing down the expected
semantics (the header field registry requires only Expert Review for