Inbox placement gets your email seen. It does not give anyone a reason to answer. That depends on who is on your list and why you are emailing them this week.
Most cold lists are built the same way: pick a job title, pick a company size, export a few thousand names. Every person on that list is a stranger with no reason to expect you. This post is about the other half of cold email: building lists from people who have already shown, in public, that they care about the problem you solve.
The list affects deliverability too
A poorly targeted list costs more than meetings. It also feeds back into where your next email lands.
Mailbox providers watch how recipients react. The strongest negative signal is a spam complaint: Google asks senders to keep their reported spam rate below 0.3%, and well under 0.1% is the safer target. Quick deletes without opening add to the picture. On the positive side, replies and “not spam” clicks tell the provider your mail is wanted.
Three spam reports in 1,000 emails is Google's limit
Spam complaints per 1,000 delivered emails, as Gmail's Postmaster Tools reports them
- At 1: Google's target, under 0.1%
- At 3: Google's requirement, under 0.3%
A list of strangers produces more of the first kind and less of the second. One bad campaign rarely sinks a domain on its own, but week after week it erodes the reputation you spent weeks building. Warmup protects the inbox. Targeting decides whether you keep it.
Public engagement is a buying signal
Your buyers tell you what they are thinking about every day, in public, on LinkedIn.
- A head of sales likes a post about falling reply rates.
- A founder comments on a competitor's product launch.
- An agency owner reacts to a thread about emails going to spam.
Each of those is a timestamped signal: this person is thinking about this topic right now. A job title tells you someone could buy. Engagement tells you they are paying attention to the problem this week.
That changes the email you send. You are no longer interrupting a stranger with a pitch. You are picking up a conversation they already started, while it is still on their mind.
Where to look for intent
Not all engagement is equal. These four sources tend to produce the warmest lists:
| Source | Who you find | Why it works |
|---|---|---|
| Your founder's profile | People who already know your name | About as warm as cold email gets |
| A competitor's company page | People who follow your category | They already understand the problem and the solution |
| An industry voice in your niche | People who learn from that person | Shared interests, often earlier in the buying process |
| Posts with your problem keyword | People actively discussing the pain | The most direct signal of a live problem |
Comments are a stronger signal than likes. Someone who writes a reply has spent effort on the topic, and often tells you exactly what they think about it.
How to build an intent list
Start by hand with one post. It costs an hour and shows you whether the approach fits your market before you invest in it.
- 1
Pick one post
From the past 7 days, on the problem you solve.
- 2
Copy the people who engaged
Open its reactions and comments and copy each person's name, title and company into a sheet.
- 3
Cut to your ICP
Remove anyone outside your ideal customer profile. Expect to cut most of the list.
- 4
Note the signal
Note what each person engaged with, and whether they liked or commented.
- 5
Find and verify emails
Find work emails with your usual email finder and verify them before sending.
One good post usually leaves you with a small but highly relevant list. If those people reply well, the next step is doing this every day across several sources, which is where manual work stops scaling. Tools like Cornersight automate it: they collect engagers from the profiles, pages, posts and keywords you choose, filter them to your ICP and add new ones daily.
However you build it, timing matters. A signal is warm for days, not months. The closer your email lands to the moment of engagement, the more likely the topic is still on their mind.
Writing the first email
Knowing why someone is on your list changes what you write. A few rules that hold up:
- Lead with the topic, not the post. “Saw you liked a post” feels like being watched. Talk about the problem the post was about.
- One idea per email. One problem, one question, one next step.
- Fit it on a phone screen. If the reader has to scroll, cut it.
- Ask a question they can answer in one line. Low-effort replies are still replies.
- Group by source. People who engaged with a deliverability post and people who engaged with a hiring post need different emails. Give each source its own campaign.
Here is the difference in practice: a CRM vendor writing to a sales leader who commented on a post about reps not updating the CRM.
Title-based list
Subject: Quick question
Hi Anna, I came across your profile and saw you lead sales at Northwind. We help sales teams close more deals with an easier CRM. Would you be open to a 15-minute call next week?
Intent-based list
Subject: the CRM nobody updates
Hi Anna, most sales leaders I speak with have the same CRM problem: reps hate logging calls, so by Thursday the pipeline report is a guess.
Is that the case at Northwind, or have you found a way to keep the data clean?
The second email never mentions LinkedIn. It talks about the problem Anna was already discussing, and asks a question she can answer in a few words.
Test it against your usual list
Don't take this on faith. Run a small side-by-side test and let your own numbers decide.
- 1
Check placement first
Run an inbox placement test on the mailboxes you will use. If the email lands in spam, a low reply rate tells you nothing about the list.
- 2
Build two lists of similar size
One from your usual title and company filters, one from engagement on a single topic.
- 3
Send from the same warmed mailboxes, in the same week
Change only the list and the angle of the first line.
- 4
Compare reply rate, positive replies and spam complaints
Replies tell you if the list was right. Complaints tell you what it cost your reputation.
If placement is good on both and the intent list replies better, you have your answer. If they perform the same, try a stronger source: comments over likes, or your own founder's audience over a competitor's.
A note on privacy
If you email people in the EU, a public like or comment is not consent. Most B2B senders rely on legitimate interest under GDPR, which means the email has to be relevant to the person's job, easy to opt out of, and honest about where you found them.
Intent lists make the first part easier, because relevance is the whole point. Keep a clear opt-out in every email, keep a record of where each contact came from, and check local rules: some EU countries require consent for commercial email even between businesses. If you are unsure, ask a lawyer before you scale.
Both halves, working together
Cold email has two jobs. The sending side gets your email into the inbox. The list side gets someone to care once it is there.
Most teams spend months on the first and minutes on the second. Flip some of that effort. Warm your mailboxes, then send to people who raised their hand in public this week. More replies, fewer complaints, and a sender reputation that gets stronger with every campaign instead of weaker.