Know Who’s Calling?

Over the past 35 years, our views on privacy and Caller ID technology have totally flipped. The concern used to be about the caller. Now, it’s the recipient.

By Ernie Smith

Today in Tedium: Congress may be mired in impeachment chatter right now, but things are still getting done in Washington, and one of those things is the passage of legislation in the House this week of a bill that aims to stop robocalls. (A form of the bill already passed in the Senate, albeit in imperfect form, so we’re pretty close to a new law!) People hate robocalls, especially on their smartphones, and the easier it is for people to detect those robocalls before they happen, the better. But I’d like to spend a little time diving into an interesting historic angle of the robocall debate. It’s hard to imagine now, but there was a time that a key functionality that makes detecting robocalls possible, Caller ID, was seen as a major privacy issue. The fact that it’s not seen as much of a privacy issue anymore reflects a major shift in public sentiment, and Today’s Tedium will spend some time analyzing that shift. — Ernie @ Tedium

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The number of robocalls made in 2019 so far, according to the tracking firm YouMail. That number—representing 164.4 calls per person—is up by around 6 billion on 2018’s 47 billion calls.

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Remember these? (Via eBay)

A company made hundreds of millions of dollars in revenue off of standalone caller ID devices in the ’90s

Sometimes, the best story discoveries come from connecting dots together, and the decision to write about Caller ID is no exception.

See, I stumbled upon this topic only because of the fact that I spotted a completely different device that is only tangentially related to the Caller ID concept.

In the late ’90s, the company Cidco (not to be mistaken with Cisco, an error many algorithms made as I was researching this) came up with a device called the MailStation, which effectively is a miniature computer only intended for use with email. Now, the MailStation on its own is interesting, and I plan to write more about it soon, but Cidco’s history is fascinating enough that it needs separate mention.

See, in the ’90s, the company was one of the biggest sellers of dedicated caller ID devices in the world—something that the world once needed for this function we don’t even give a second thought on our smartphones. The MailStation, which is also incredibly fascinating, was its follow-up product.

Founded in 1988, the firm was built specifically around the then-new Caller ID technology, which had yet to emerge nationally. (Its name literally stands for Caller ID Co.)

This may sound like a really specific niche, but it turns out that there are a lot of phones, and nearly all of them needed access to this information. Per a 1996 San Francisco Chronicle article, the company had sold 9 million products by that point, earning $194 million in revenue by that point, along with a 60 percent market share. This, despite the fact that the device was literally just an LCD screen with a board that could interpret a code built by the phone companies.

The secret to the firm’s success was a mixture of great timing (it was to the market well before just about anyone else) and the fact that it had worked with the Baby Bells to distribute the devices.

“We have a quality-control record second to none,” said the firm’s marketing director, Dayna Nielsen, in comments to the newspaper. “The defect rate is less than one-third of 1 percent.”

Per Hoover’s Handbook of Emerging Companies, the company’s partnerships played a big role in the success of Caller ID, which, in some markets, had uptake of as much as 20 percent.

Clearly, it had hit a nerve as a concept, even though it wasn’t overwhelmingly widespread. But Caller ID, despite its benefits, was looked at with skepticism by some before it became a fact of life.

“Look at these calls, and tell me I’m not crazy.”

— Belinda Hines, a Detroit-area woman who ran into a bizarre situation in 1995 where her Caller ID device, made by Cidco, appeared to display phone calls from a number of former presidents and historic figures, including John F. Kennedy, Thomas Paine, John Hancock, and Abraham Lincoln. As the Detroit Free Press noted, it led to concerns of something paranormal happening, but the truth is that it was likely something more innocuous: The founder of Cidco, Paul Locklin, was also listed as a prior caller, so it’s likely a series of test numbers showed up.

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When Caller ID was first introduced, people were most concerned about the privacy of the callers

In 1987, when New Jersey Bell first tested out its Caller ID offering, it was sold to the public as a huge form of convenience for users—which is generally how it’s seen today as we try to avoid robocallers bugging us at all hours.

But during this period when the artists in this upcoming tour were at the top of their game, Caller ID was actually seen as a privacy risk not for the recipients of the phone calls, but those dialing.

Part of the issue, as the Los Angeles Times noted in 1990, was that it actually created major headaches for the public at first, in part because of bad actors who took advantage of the system when it was still new.

Remember in the 1980s and 1990s when people were frequently encouraged to call 1-800 or 1-900 lines to access some sort of hotline or something similar? Well, it turns out that some of the sketchier telemarketers out there were misusing a related technology, Automatic Number Identification. Per the L.A. Times, these marketers would gather up callers’ phone numbers, match them to a database, and then reuse that information for future pitches, getting a full profile of you.

Caller ID was not nearly that advanced, but it did create problems for people in sensitive situations—say, police informants or drug dealers. (Good thing for burner phones.) Even those in less sensitive situations, like doctors or teachers, didn’t like the new technology because it exposed the fact that they often made phone calls at home. And it should be emphasized that this was still during a time where phone books were common, meaning that a phone book could also expose a person’s address. (A related service, called “call trace,” allowed people to track a caller’s information after they made a threatening or malicious call.)

And this led to often tense situations. Perhaps the most notable example of this came from Pennsylvania, where the local chapter of the American Civil Liberties union successfully sued the state to prevent the spread of Caller ID unless there was an option for the public to disable it easily and for free.

But the fact is, Caller ID was the perfect solution for the Moe Szyslak problem. You know the one, where people take advantage of public phone lines and jam them up with misleading or even prank calls.

And this very point was often promoted in commercials for these services, showing how caller ID could successfully foil a prank caller who was messing with someone’s mom for kicks.

And even blocking the phone number on the caller’s end was often enough to get people to question the source, as it was listed as “private” rather than “unlisted.”

So, in many ways, you could see the benefits all around—as could outside observers. Famed New York Times columnist William Safire gave his view of the technology in 1989. Safire, a self-described privacy nut, saw the issue from both ways, both as an “electric peephole” and coming with an inherent “loss of privacy.” His answer to the problem, accordingly, was fairly balanced:

We do not have the choice of stopping Caller ID. That’s already selling through local phone companies. We do have a way to set a thief to catch a thief, however: that’s called “Caller ID block.”

Companies selling the ID service should sell customers the ability to protect their numbers from appearing on the screen of the people they call. (It’s a great business; the phone companies get you both ways.) Say I have Caller ID, and you call me, but you don’t want me to have your number. You activate your Caller ID block; I look for your number and it’s not on my screen. Ho-ho, say I, it’s one of those jokers who has my number but doesn’t want me to have his or hers; I won’t answer.

That, it seems to me, levels the privacy field. You don’t have to share the secret of your identity in advance with me and I don’t have to take your call. Give nuthin’, get nuthin’.

Safire’s essay drew a number of letters to the editor, by the way, including some that questioned the high costs of the technology for consumers on both ends.

This debate, honestly, could have gone either way. But a few key concessions—including the option to block Caller ID on individual calls using the *67 code—helped ease the uptake of Caller ID in a way that felt agreeable.

But the key thing is that the benefits of privacy for the recipient started getting more attention over time.

Case in point: One of the biggest hits of 1995, No Doubt’s “Spiderwebs,” featured a protagonist, Gwen Stefani, who was screening her phone calls—something made easier with Caller ID. And after the release of the movie Scream, which prominently featured the technology, Caller ID use exploded.

The public figured out that the person whose privacy needed the most protection was not the caller, but the recipient.

And once that point clicked, Caller ID became fairly normalized. It even became a common feature of cordless phones and, later, smartphones—meaning that there was no need for a dedicated Caller ID device anymore.


The amount Earthlink purchased Cidco for in 2001. The company, which later marketed the MailStation devices, had mostly moved away from caller ID devices by this point—despite once being a major income source for Cidco, the firm went all in on internet devices—presumably in part because many phones had caller ID built in by the early 2000s, making standalone caller ID devices redundant.

These days, our privacy is spread out in many more dynamic places than just our phone number. Our IP address, our purchase history, the websites we’ve viewed? It’s all on display.

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(Dan Dickinson/Flickr)

The dedicated Caller ID device, despite being around today, feels like something that might struggle in this modern context.

Certainly it’s way easier to block your number on a modern smartphone, but because of shifts in the telephone market, it’s also harder to figure out what’s a robocall and what’s not. Voice over IP, or VoIP, has helped turn robocalls into a game of cat and mouse. When a Caller ID is spitting out fake or unexpected numbers, the integrity of the whole system is screwed.

Fortunately, the phone industry is working on this, with the help of the Federal Communications Commission , which is pushing a two-part solution called STIR/SHAKEN (or SHAKEN/STIR). The STIR part refers to telephone identity standards that the phone industry follows, while the SHAKEN part refers to a token-based signature system.

While the standard won’t do everything, it shows that the phone industry is upping its game as the problem gets more serious—something also reflected by the new law, which requires phone companies to take steps to verify and block calls. And strangely enough, if we didn’t have Caller ID in place, this problem would be about a thousand times worse.

Good thing we bought all those devices back in the ’90s.


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Editor’s Note: After publication, this piece clarified the reference to phone-screening in “Spiderwebs” and added a reference to the movie Scream, which helped to popularize the technology.

Ernie Smith

Your time was just wasted by Ernie Smith

Ernie Smith is the editor of Tedium, and an active internet snarker. Between his many internet side projects, he finds time to hang out with his wife Cat, who's funnier than he is.

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