No platform owns every variable that determines delivery or placement. A useful responsibility model says who can control each decision, what evidence they can see, and where the system must stop.
Responsibility matrix
| Area | MailSequence | Customer/sender | Mailbox providers |
|---|---|---|---|
| Domain identity | Automate and validate supported DNS setup | Own the domain; disclose every legitimate sender | Evaluate authentication and alignment |
| Mailbox connection | Request scoped access; test sync and SMTP readiness | Authorize the account; secure users and credentials | Issue access, limits, restrictions, and responses |
| Audience | Verify addresses and enforce stored suppression | Choose lawful, relevant recipients and preserve provenance | Accept, defer, reject, filter, and collect recipient feedback |
| Message | Provide sequence and personalization controls | Approve truthful identity, claims, links, and opt-out language | Apply format, safety, policy, and spam filtering |
| Volume | Enforce configured inbox/domain caps and sender eligibility | Choose conservative limits across every sending system | Apply published and undisclosed service or abuse limits |
| Intervention | Pause, suppress, cool down, and surface evidence when configured | Investigate, correct, and decide whether to resume | Throttle, restrict, reject, or change placement |
What MailSequence is responsible for
- Keeping product claims, supported providers, limits, and documentation accurate.
- Protecting stored credentials and enforcing tenant-scoped access.
- Validating the supported DNS path and showing authentication status.
- Testing mailbox readiness before campaign eligibility.
- Applying verification, suppression, capacity, reply-aware stopping, and health controls as documented.
- Keeping warmup evidence separate from campaign engagement and distinguishing observed from simulated warmup signals.
What the sender is responsible for
- Owning or being authorized to use every domain, mailbox, audience, claim, and linked destination.
- Knowing why each recipient is appropriate and complying with the rules that apply to the outreach.
- Approving accurate sender identity, message content, personalization, and unsubscribe behavior.
- Accounting for mail sent outside MailSequence when setting mailbox and domain capacity.
- Reviewing warnings, provider responses, complaints, bounces, and changes before resuming.
- Securing user accounts, mailbox-provider administration, and customer-owned integrations.
What mailbox providers control
Google, Microsoft, Yahoo, and receiving systems set authentication requirements, service limits, abuse controls, reputation models, throttling, restrictions, and filtering. They can change these systems and do not guarantee that compliant mail will reach the inbox.
Published requirements set minimum conditions. Meeting them improves attribution and removes preventable failures. Providers still evaluate sending history and recipient feedback.
What recipients control
Recipients decide whether a message is useful, whether to reply, unsubscribe, block the sender, or report spam. Their expectations can differ from the sender's intent. No infrastructure or copy tactic can remove that agency.
A practical operating handoff
- MailSequence surfaces a concrete warning or enforces a documented stop.
- The operator identifies the affected contact, inbox, domain, campaign, provider, and time window.
- The sender reviews audience, message, policy, provider, and external-system evidence.
- The responsible owner corrects the root cause and records the decision.
- MailSequence retests the controls it can observe.
- The operator resumes at lower volume only when the evidence supports it.
MailSequence provides sending and workflow software. Customers remain responsible for legal compliance, audience permission, and provider acceptance. Inbox placement will vary.
Primary sources
- Google: Email sender guidelines
Sender, provider, infrastructure, authentication, volume, complaint, and service-provider responsibilities. - Yahoo Sender Hub: Sender best practices
Authentication, complaints, unsubscribe, and recipient-expectation requirements. - Microsoft: Outbound spam protection
Customer configuration, provider restrictions, and bulk-mailing limitations. - MailSequence security
Product-specific credential, access, API, webhook, and audit-control boundaries.