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Google accused of stomping on rivals as it stamps out annoying Calendar spam

Talk about going against the Grain

Google recently changed the default setting for adding invitations to its Calendar service in a way that interferes with third-party products. The Big G said it's just trying to block spam while some in the industry are calling foul.

Earlier this week, Mike Adams, CEO of Grain, an organizational service for managing customer relationships, complained openly about the change. He accused Google of trying to kill third-party appointment booking services like Calendly in favor of Google Calendar, part of the web giant's Workspace portfolio.

Google last March expanded appointment scheduling to a broader set of Workspace editions and recently has been trying to monetize the service to add shareholder value.

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In July, the ad giant announced the addition of "an option to display events on your calendar only if they come from a sender you know." The Chocolate Factory's rationale was to provide a way to reduce invitation spam, a persistent concern among those using Calendar or any service that supports permissionless interaction.


At the time, according to Adams, the default setting was to show invitations from everyone. But recently that was changed to adding invitations "only if the sender is known."

Google, said Adams, recently revised most users' default setting to not show third-party invitations in Calendar unless the booker previously emailed the host, or explicitly accepted the invitation in email.

The setting change was launched in November 2022 as an opt-in but Google began gradually rolling out the default change in January in order to monitor for feedback.

Feedback surfaced in February when some users reported seeing a notification in Calendar, and in the months that followed as reports of missed bookings came to light.

Their timing is suspicious and their explanations don't hold water

This small reconfiguration has thrown a wrench into services based on permissionless appointment booking and adds more friction to business communication, Adams contends.

"And of course this 'spam prevention' measure doesn't apply to meetings booked through their own new competitive software, which naturally doesn't support any video meetings options but Meet," he said.

Asked about whether it's correct that these changes do not affect Google appointment scheduling, a spokesperson for the Big G said it's not. We're told that the spam protection applies to unknown senders regardless of service. So a Calendar invitation from an unknown personal Gmail account would not appear automatically.

Reached by phone, Adams said Grain uses Calendly internally and encountered problems with invitations after the setting change. But when he tried the same thing in Google's appointment scheduling system, it worked properly. He said he doesn't believe Google is being forthright about the situation

"My goal is to encourage Google to be decent and fix it," he told El Reg. "We have better things to do than deal with anticompetitive nonsense. Their timing is suspicious and their explanations don't hold water."

Part of the issue may be that within an organization, all Workplace email addresses should be known, so any intra-company invitations would work for Google appointment scheduling. That's not necessarily the case for third-party service providers that don't have as much access to Gmail identity data.

Google's appointment scheduling only supports invitations from users, and not from generic or no-reply addresses, which isn't the case for many third-party services.

The new default, said Adams, is causing major problems for Grain, where users book time and then miss appointments because the event never showed up in their calendar.

"These moves are so blatantly anti-competitive and anti-consumer ... all under the guise of 'spam prevention' ... which they could easily manage for Google accounts using third-party booking software," he said.


On Thursday, Calendly, a third-party appointment booking service, published a help center message about Google Calendar's new default. It advises customers about the setting's changes and how to alter them.

In a statement emailed to The Register, Calendly CEO and founder Tope Awotona said, "We're aware of the recent changes Google made to its users' default calendar settings to reduce spam and unwanted invites. We're working closely with our customers and partners to understand and mitigate the impact through product enhancements and education and will continue to provide updates as we evolve the platform."

Awotona expressed confidence that Calendly will be able to provide safe and secure scheduling automation.

We are committed to following best practices for keeping users safe, and also support interoperability and user choice for all apps

Adams argued that Google should have just left the default as it was and allowed people beset by spam to change their setting as needed.

A Google spokesperson told The Register, "To reduce the risk our users face from unwanted calendar spam, we introduced a default in Calendar to safeguard users from unknown senders. These efforts have already posted strong results, dramatically cutting back malicious calendar invites. We are committed to following best practices for keeping users safe, and also support interoperability and user choice for all apps."

That commitment, we're told, involves further adjustments to user controls and the expectation is that these tweaks will address at least some of the concerns raised by third-parties.

Google is looking at ways to improve trust signals when an invitation arrives from a generic or no-reply address in a way that does not dilute spam protection. This could take the form of a warning banner when customers have received an invitation from a generic/no-reply address, though that's not decided yet. ®

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