In every company, there are people who keep the organization running behind the scenes.
They are the ones who immediately say, "You might be on mute," during an online meeting when someone's mic isn't working. They are the ones who speak up at the end of a meeting when no one else will and ask, "So, when are we doing this next?" And they are the ones who add a stamp (emoji reaction) to everyone's posts on the internal chat.
Today, I want to talk about that third type of person. It's about Slack stamps—a theme so small that no one has ever seriously discussed it. I've decided to call this "Slack Stamp Studies."
You might think I'm exaggerating, but the way stamps are used reflects everything from an organization's power structure to its psychological safety. Below, I will discuss Stamp Studies across four fields: Functional Theory, Organizational Development Theory, Political Science, and Misunderstanding Theory. Since I'm calling it a "study," I'll proceed while citing previous research (in the form of various company blogs and X posts).
Functional Theory: Why are stamps used?
First, the basics. Slack stamps (accurately called emoji reactions, or "reacjis" by Slack) have four major functions.
Function ①: A substitute for "Read" receipts
Slack does not have a "read" mark like LINE. This can be seen as a design philosophy to avoid the pressure of "I have to reply now that I've read it," but as a side effect, it drops us into a triple-choice purgatory: "Was it read? Was it read and ignored? Or has no one seen it at all?" Stamps fill this void.
Function ②: Noise reduction
According to Slack's blog, before the reaction function existed, a single post would be cluttered with replies like "Understood," "I'll check," and "Thank you." It's quite poetic to think that the company created stamps because they couldn't stand the noise of their own tool.
Since typing "Understood" every single time is a waste of time, being able to complete it with a single stamp is extremely convenient.
Function ③: Securing emotional bandwidth
This is the main theme of this article. With remote work, we have lost nodding, back-channeling, and even the disinterested "hmm." The non-verbal information that once filled meeting rooms has been wiped out, and the only survivors are the emojis in the corner of the screen. In other words, stamps are the last survivors of lost human body language. Does that sound like an exaggeration? Judge for yourself after reading the next part.
Organizational Development Theory: The "Stamp Uncle" is an unpaid Org Dev Consultant
In internal chats, there are people who put stamps on everyone's posts. On a newcomer's first daily report, on a dry announcement from general affairs, and even on those "posts no one seems to read" at 5 PM on a Friday.
What these people are doing isn't just reacting. They are sending a signal: "I see you," and "You are not alone." With a single stamp, they reduce the sender's loneliness, lower the hurdle for speaking up, and warm the organization's atmosphere by a fraction of a degree. I call this "Micro-Organizational Development." You don't need personnel system reforms or engagement surveys. Just press a stamp. It's a message to you from a fingertip.
For those who think this is just "spiritualism," I've brought data.
A study presented by Ferguson et al. at CHI 2024 titled "No Risk, No Reward: Towards An Automated Measure of Psychological Safety from Online Communication" analyzed about 13,000 Slack messages from teams with high and low psychological safety. They looked for where that sense of security appears in the logs.
The results were quite suggestive:
- Teams with high psychological safety had a higher rate of replies to posts (18% vs. 12%), abundant emoji reactions, many playful custom emojis (like members' faces), and participation wasn't biased toward specific people.
- Meanwhile, there was no significant difference in the keywords used in the messages themselves.
- In short, team health is shown not by what was said, but by how people reacted to each other.
My personal favorite finding is that low-psychological-safety teams also used emojis frequently, but their usage was for warnings like "⚠️". It's not just about using emojis; it's about which emojis are flying around. Does your channel have more "🎉" or "⚠️"?
Note that the study was exploratory and based on two teams, so we should be cautious about generalizing. Stamp Studies is a rogue discipline, but it's the type of rogue that honestly reports the limitations of its sources.
There are people who practice this insight without being asked. This article is interesting:
Recommendations for reactions that improve team atmosphere
According to this article, staff who improve the team atmosphere:
- Attach positive reactions constantly.
- Attach them as immediately as possible.
- Attach them even if the post isn't directed at them.
It's so thorough you'd think it was in their job description. A sharp point in the article is that continuing to react positively in an open space forms a norm that tells everyone "this is the kind of behavior that is praised in this team." You might mockingly call them a "Stamp Uncle," but they are doing the same work an org dev consultant sells for tens of thousands of yen an hour.
And here is the most important theorem of Organizational Development Theory: Stamp culture only grows from the top down.
Casual stamps require courage for younger employees. Can a newcomer put a casual "Got it" stamp on a director's post? No. That's why people in high positions should actively use casual stamps. When the bosses use them, younger staff gradually start to feel comfortable using them too.
Conversely, in an organization where the director only ever uses "👍", the members will never branch out. The moment an executive uses a silly custom stamp, that stamp becomes "safe to use" company-wide. Dignity decreases by 1 millimeter, and reports increase by 10. It's a clear profit.
Political Science: You are stamping "Who said it," not "What was said"
From here, Stamp Studies enters the darkness.
For a long time, I thought stamps were attached to the "content" of a post—as a sign of reading or agreement. In other words, I thought stamps were given based on what was written.
I was wrong. There are many people who give stamps based on who wrote it.
For example, in one channel I observed, a newcomer on their third day posted an incredibly high-quality research memo. However, only a few stamps were attached. Thirty minutes later, an executive posted this bit of "poetry":
I just thought of this, but work is really all about "human connections," isn't it? Let's value the customer's perspective more. Customer perspective, customer perspective.
A massive number of stamps like 🙏👏✨💯S followed. Looking closely at the people stamping, they were all people who had been flattering that executive for a long time.
In terms of Stamp Studies, this is a phenomenon where the organization's power structure leaks into the stamp section. The distribution of stamps cruelly and accurately visualizes everyone's unconscious calculation of "whose posts are beneficial to react to." And they aren't even aware of it. The people who stamped the executive's poem didn't think they were sucking up; they thought, "I just felt like it was good." To them, Slack is just another social network like Facebook or Instagram. The stamp section is where organizational sycophancy crystallizes.
On the other hand, let's look at it from the perspective of the newcomer who made a useful post but got no reactions. Seeing their hard work ignored while the executive's poem is celebrated, they will likely think, "This is stupid, I'm not sharing anything anymore." The organization loses a source of high-quality input, and that loss doesn't show up on any KPI. What a waste.
Misunderstanding Theory: Stamps that cause accidents despite good intentions
It's not enough to just press stamps. Stamp Studies has an important sub-field called "Misunderstanding Theory," where accidents happen daily. Let's examine two representative accident cases.
I have written the rest on Note, so please take a look if you'd like.
Note: Slack Stamp Studies
