Deliverability briefing, Monday, 31 August 2026
thermofisher.com switches mail filter to Proofpoint, Zoho tightens SPF setting
Two real companies moved overnight: thermofisher.com switched its mail filter to Proofpoint, and Zoho Mail turned on a stricter address-check setting. No new deliverability story cleared two outlets today, so these company-level moves carry the news. Neither change affects how your own cold email is judged, but they show gateways keep shifting under real senders.
Inbox Rules Index
499 of 499 companies checked, Monday, 31 August 2026
Every morning we look up the published email settings of the same 499 real companies, the kind you send cold email to. This is what they have set up, not a score on your own sending.
Today's check covers all 499 companies in the panel. 88.4% of them block mail that fakes their own address, unchanged from the last check and up 0.6 percentage points from the 10 August baseline. That's a read on how seriously these companies run their own email security, not a signal about how your cold email will be treated.
What this means for your sending
Proofpoint screens more of these companies than anything else, at 33.9%, so it is the filter most of your cold email actually meets. 6.2% ask senders for an encrypted connection, so an expired or mismatched certificate on your sending server can stop mail reaching them at all. 2.4% cannot receive email at all, which is dead weight on any list that includes them. The rest is about how these companies stop others forging their address. It is a good sign of how seriously they run email security, but it is not what decides where your mail lands: that is judged against your own domain's records.
Who changed their setup
| thermofisher.com | Spam filter: Their own servers, or unknown → Proofpoint | switched |
| zoho.com | Sender list: nothing published → locked list | stricter |
2 of these companies changed their email setup since Friday, 28 August 2026: 1 got stricter. If any are on your list, the stricter ones are running their email security actively.
Whose spam filter your email meets
| Proofpoint | 33.9% | |
| Microsoft 365 | 26.1% | |
| Google Workspace | 18.8% | |
| Their own servers, or unknown | 9.6% | |
| Mimecast | 4% | |
| Cisco Secure Email | 3.8% |
Proofpoint screens about one in every 3 of these companies, more than any other filter. This is the software that reads your email before a person does, and it is the part of this briefing that most directly decides whether you land.
Which industries guard their name hardest (companies checked)
| Software (126) | 97.6% | |
| Finance (54) | 94.4% | |
| Services (28) | 92.9% | |
| Healthcare (47) | 89.4% | |
| Logistics (17) | 88.2% | |
| Retail (50) | 88% | |
| Travel (25) | 88% | |
| Energy (24) | 87.5% | |
| Media (26) | 84.6% | |
| Telecoms (30) | 80% | |
| Industrial (44) | 79.5% | |
| Schools and universities (28) | 57.1% |
Software guards its name hardest: 97.6% block mail faking their address. Schools and universities least, at 57.1%, a gap of 40.5 points. A high number means that industry runs email security tightly, so expect your own setup to be looked at more closely there.
All 499 of the 499 companies we check answered today. The same real companies every morning, looked up in public DNS. This is what the people you email have set up, not a score on your own sending.
What these numbers mean
Does a high rate of blocking forged mail mean my cold email will get rejected?
No. A company's setting for blocking forged mail only covers messages sent pretending to be them. Your cold email is judged by your own domain's settings, not theirs. Today 88.4% of the panel had that setting turned on, and it says nothing about your own deliverability.
What changed at Zoho Mail today?
Zoho Mail moved its sender verification setting from missing to strict, according to Emailchaser's daily check. That means outside servers can no longer send mail claiming to be from zoho.com without failing a check. It does not affect mail Zoho customers receive from you.
What mail filter reads the most business email today?
Proofpoint sits in front of 33.9% of the panel, ahead of Microsoft 365 at 26.1% and Google Workspace at 18.8%. These are the gateways that actually scan your message before any inbox decision, so knowing which one a prospect runs matters more than their internal security settings.
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