Treasure Ship email service provider (ESP)
According to Live Direct Marketing's daily Tranco top-1M scan (September 12, 2026), Treasure Ship is the email service provider (ESP) for 133 domains — 0.02% of 629,828 SPF-publishing domains. Detection method: include: mechanisms in the SPF record.
Key facts
- 133 domains in the Tranco top-1M use Treasure Ship (0.02% of SPF-publishing domains).
- Snapshot date: 2026-09-12 — recomputed every day.
- Strongest TLD: .jp (41.4% of its domains).
- Most co-used service: Unknown / Other.
- Directory category: email service provider.
Why Treasure Ship appears in this category
Treasure Ship — Japanese email marketing service.
We classify it as a email service provider from include: mechanisms in the SPF record matching a maintained provider rule. This is infrastructure attribution from public DNS, not evidence of a direct contract or exclusive use.
Treasure Ship is an email service provider identified through SPF include mechanisms across sending domains. Primarily serving Asia-Pacific markets—particularly in Japan—it delivers email for a dispersed set of smaller websites across numerous international TLDs, rather than a concentrated set of major brands.
For email professionals, Treasure Ship exemplifies the infrastructure landscape of the long tail: smaller, regional ESPs whose presence in SPF records and email headers is observable but whose brand recognition and documented reputation may be limited. Understanding Treasure Ship's role in this category is essential for anyone evaluating the full sending ecosystem.
Where Treasure Ship sits in the Tranco ranking
| Tranco rank band | Domains | Share of its base |
|---|---|---|
| Top 1,000 | 0 | 0.0% |
| Top 10,000 | 1 | 0.8% |
| Top 100,000 | 11 | 8.3% |
| Top 1,000,000 | 121 | 91.0% |
| Unranked | 0 | 0.0% |
Top-level domain split
| TLD | Domains | Share | |
|---|---|---|---|
| .jp | 55 | 41.4% | |
| .com | 37 | 27.8% | |
| .co.jp | 34 | 25.6% | |
| .net | 4 | 3.0% | |
| .or.jp | 2 | 1.5% | |
| .info | 1 | 0.8% |
What Treasure Ship users also use
Cross-tabulated from the same daily snapshot — the other email services seen on the same 133 domains.
| Type | Service | Domains | Share of Treasure Ship users |
|---|---|---|---|
| Mailbox | Unknown / Other | 45 | 33.8% |
| Mailbox | Microsoft 365 | 27 | 20.3% |
| Mailbox | Self-Hosted | 20 | 15.0% |
| Mailbox | Google Workspace | 19 | 14.3% |
| Mailbox | Kagoya (JP) | 3 | 2.3% |
| Mailbox | Trend Micro | 2 | 1.5% |
| ESP | Amazon SES | 44 | 33.1% |
| ESP | BizMatrix | 12 | 9.0% |
| ESP | Repica WebCAS | 9 | 6.8% |
| ESP | FSI Email Security | 6 | 4.5% |
SPF configuration and long-tail ESP patterns
Treasure Ship's SPF-mediated presence across diverse, smaller websites represents a characteristic pattern of long-tail ESP infrastructure: decentralised, often less well-documented than tier-one providers, and frequently grouped with unknown or unclassified sending sources. This pattern has deliverability implications: receiving systems may struggle to correlate SPF includes with reputation signals when the sending provider lacks strong brand identity, and administrators may need to evaluate Treasure Ship's infrastructure based on empirical sending behaviour rather than established reputation databases.
See the full Treasure Ship data page (KPI cards, trend, sample domains) →
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Frequently asked questions
What is Treasure Ship and why might it appear in my domain's sending infrastructure?
Treasure Ship is a smaller email service provider primarily serving Asia-Pacific markets, whose infrastructure is integrated into sending chains via SPF includes when organisations use its platform for email delivery.
How many domains use Treasure Ship?
133 domains in the Tranco top-1M use Treasure Ship as their email service provider (ESP) as of September 12, 2026 (0.02% of SPF-publishing domains), according to Live Direct Marketing's daily DNS scan.
Is Treasure Ship common enough to affect email deliverability testing?
Treasure Ship accounts for 0.02% of SPF-publishing domains in the top 1M. Whether you should seed a test mailbox there depends on how much of your audience it represents — the co-usage table above shows the services it appears alongside most.
Which countries or TLDs use Treasure Ship most?
Treasure Ship's largest TLD is .jp (41.4% of its domains); it appears across 6 TLDs in total.