A placement report becomes easier to use when each term names one observable stage or technical object. Delivery, Inbox, authentication, reputation, and engagement are not synonyms. Use this glossary with the product's own methodology and your sending service's event definitions. When a label is ambiguous, identify the copy, checked object, timestamp, and evidence behind it before choosing an action.
Transport terms: submitted, accepted, deferred, rejected
Submitted means the message was handed to a particular system; name that system because application submission and remote acceptance are different stages. Accepted describes a successful receiving-server handoff under the relevant event definition. It does not guarantee the user's primary inbox or establish that the recipient opened the message.
Deferred refers to a temporary transport failure, commonly associated with an SMTP 4xx response and a possible later retry. Rejected refers to a permanent failure for the attempt under its response conditions, commonly represented by 5xx. Always retain the exact response text and stage. These broad classes guide investigation but do not identify every detailed cause.
Observation terms: received, missing, unavailable, pending
Received means a matching copy was detected under the observer's matching rules. A not-found or missing result follows a successful relevant mailbox search without a matching copy at that time. It does not identify a folder or prove a rejection. Check destination, submission, transport, timing, and matching when investigating it.
Unavailable means the relevant evidence could not be obtained, such as when a mailbox cannot be read. Pending means work has not finished. Unknown means a conclusion cannot be established from available evidence. Failed must name the operation or check that failed. None of these states should automatically become Spam in a summary.
Folder terms: Inbox, categories, Spam, history
Inbox is the observed inbox destination under the product's documented grouping. Primary and Promotions can describe Gmail inbox categories; Focused and Other can describe another client's prioritization. Keep the original labels and mapping. A business objective limited to Primary is a separate definition from treating all other categories as unwanted mail.
Spam or Junk identifies the corresponding observed unwanted-mail destination. Folder history records observations of the same matching copy over time. In LDM's copy-level monitoring, elapsed observation begins at the copy's first receipt or detection. A later checkpoint is not a resend and does not test a newly edited template.
Identity terms: From, envelope sender, SPF, DKIM, DMARC
From is the visible author address. The SMTP envelope sender is the transport return identity, commonly reflected in Return-Path on a delivered copy. SPF evaluates the relevant SMTP identity against connecting infrastructure. DKIM validates a signature associated with a signing domain. DMARC relates an applicable passing authentication result to the visible author domain through alignment.
Authentication-Results records a receiver's authentication findings, subject to the trusted-boundary rules for that header. A published DNS record is configuration evidence; it is not automatically proof that a particular message passed. Successful authentication establishes its own technical facts and does not guarantee that the receiver considers Inbox delivery desirable.
Measurement terms: denominator, coverage, reputation, engagement
A denominator is the population used below a rate's dividing line. LDM's ordinary Inbox percentage uses observed external received copies. Coverage describes how much of the intended test set supplied relevant evidence. Internal controls, missing copies, and unavailable checks must remain visible without silently changing the placement formula.
Reputation concerns a receiver's assessment of identities and behaviour, with coverage specific to the evidence source. Engagement concerns recipient actions and interest. Neither is directly measured by a seed folder alone. When reviewing a report, keep those audience and provider signals separate from the controlled copy's observed destination.
Frequently asked questions
What should I do when two reports use different terms?
Compare definitions, raw counts, provider labels, and timestamps before comparing headline values. Different vocabularies can conceal different measurements.
Does a green label approve the next campaign?
Only within its stated scope. Identify what passed, on which copy and route, and what the planned campaign changes before extending the conclusion.
Which terms belong in an escalation?
Use exact event and folder names, response codes, checked identities, and UTC times. Precise records help support distinguish a transport issue, observation gap, and confirmed placement problem.
Sources and scope
Source check: November 5, 2026. Source checking is separate from publication. Observations apply to the tested copies and conditions.