Privacy policy
This policy covers three things: the short links at read.solsticelabs.com; how we measure our advertising for The Solstice Letter, our newsletter on Substack; and Solstice Ads, an internal tool we use to manage our own advertising. How Substack itself handles your subscription is governed by Substack's privacy policy. This policy does not cover the website solsticelabs.com.
The short links at read.solsticelabs.com
A link such as read.solsticelabs.com/the-crop-report-3-1 forwards you to a Solstice letter, note, article or the book page. Before forwarding, it adds labels to the address that say where the link was shared, for example which social network or email campaign, so that we can count how many readers each channel sends.
Some links record the click in Google Analytics before forwarding you. Google Analytics may set cookies and process your IP address and device information under Google's privacy policy. We see only totals and counts. We do not collect your name or email address through these links, we do not store anything about you ourselves, and we keep no log of individual clicks.
Newsletter subscribers and advertising measurement
If you subscribe to The Solstice Letter on Substack, Substack gives us your email address and country. Our Substack pages also carry Meta's pixel, which tells Meta when a visitor signs up.
To measure our advertising on Meta (Facebook and Instagram) and to help it reach readers like our subscribers, we send Meta a hashed version of subscribers' email addresses, together with the time they subscribed and whether they have opened or read any of our letters. Hashing scrambles the address one way before it leaves our systems. We do not send names, unhashed addresses, or which letters you read. Meta matches the hashed addresses against its own accounts and handles the data under its Business Tools Terms.
We do not send this data for subscribers in the European Union, the European Economic Area, the United Kingdom or Switzerland. To opt out, write to osh@solsticelabs.com and we will exclude your address.
We do not sell personal data. The only transfers to third parties are those described in this policy: to Google Analytics for the short links, and to Meta for subscribers as set out above.
Solstice Ads
Solstice Ads is an internal application used only by the Solstice Laboratory team to create, manage and report on our own Google Ads account. It signs in with Google on behalf of our own team members and reads and changes only our own advertising data: campaigns, budgets, keywords, ads and their performance.
It does not access the Google accounts or data of anyone outside our team, does not collect information about people who see or click our ads beyond the aggregate performance figures Google Ads provides to every advertiser, and does not sell, share or transfer any data to third parties.
Solstice Ads's use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements. Access can be revoked at any time from the Google account's third-party access settings.
Retention and security
Advertising data retrieved by Solstice Ads is used to produce our internal reports and is kept only as long as those reports are useful to us. Sign-in credentials are stored in the operating system's secure keychain on our own machines and are never published.
Contact
Questions about this policy or requests about your data: osh@solsticelabs.com.