TIERS Insights
Choosing Between Native Exports, Load Files, RSMF, and Portable Reports
A practical comparison of common digital-evidence delivery formats and the questions counsel should resolve before choosing one.
No single digital-evidence format is best for every matter. The right choice depends on what must be reviewed, which metadata matters, how relationships should be preserved, whether counsel needs a self-contained report, and what the receiving platform can ingest.
Choosing a format after processing is complete can force rework. The examiner, litigation-support team, and review provider should agree on the intended use before the final export.
Native files
A native delivery provides files in their original or exported application format, often with a metadata table or source inventory. Natives can preserve functionality and content that images cannot, such as formulas, hidden spreadsheet cells, embedded objects, media, and application-specific structure.
Useful when: reviewers need original functionality, a relatively small focused set is being delivered, or the hosting platform will process the files.
Watch for: filenames that changed during export, missing source paths, loss of parent-child relationships, unsupported proprietary formats, malware risk, password protection, and the absence of a consistent field map.
Load files for Relativity or another review platform
A load-ready package typically combines metadata, extracted text, native-file links, image references, and document identifiers in a structure the review platform can import. Common components may include delimited metadata files, OPT-style image references, native folders, text folders, and a delivery manifest.
Useful when: the data will enter a hosted review workflow, field mapping and document relationships matter, and counsel needs scalable search, coding, analytics, or production.
Watch for: delimiter and encoding issues, inconsistent dates, time-zone handling, invalid paths, duplicate identifiers, missing text, broken family relationships, field-length limits, and specifications that differ between hosting providers.
RSMF and structured messaging formats
Relativity Short Message Format and comparable structured representations are designed to preserve chat and messaging context. They can organize participants, messages, timestamps, attachments, reactions, edits, and conversation boundaries in a form suitable for review.
Useful when: the evidence includes Teams, Slack, text messages, or other conversational data where message-by-message natives would destroy context.
Watch for: source exports that omit deleted or edited records, unclear time-zone conversion, unsupported reaction types, attachment-link failures, very large conversations, duplicate messages, participant normalization, and whether the source data supports all desired fields.
UFDR and Portable Case Reports
Mobile forensic tools can create self-contained reports or portable review packages that allow counsel or an investigator to browse selected device content without using the full forensic platform. These can be efficient for targeted review and preserve links between related mobile artifacts.
Useful when: the audience needs a controlled, searchable view of selected mobile evidence, the matter does not require review-platform ingestion, or a preliminary consultation package is needed.
Watch for: proprietary viewer requirements, very large package sizes, data included by default, redaction limitations, report-generation settings, viewer version compatibility, and whether the report represents parsed artifacts rather than the complete underlying source.
Tagged or “export tags only” packages
A focused tagged export includes only records an examiner or reviewer selected, often with related metadata and attachments. It can provide a manageable case subset and avoid sharing broad extraction results.
Useful when: counsel wants a curated evidentiary set, a briefing package, or a limited transfer to another expert.
Watch for: selection bias, lost surrounding context, omitted nonresponsive but explanatory records, inconsistent tagging criteria, and the need to preserve a defensible path back to the full examination.
Images and PDF reports
Rendered images or PDF reports are easy to view and cite, but they may flatten dynamic content, hide metadata, separate attachments, and limit search or analytics. They are often best as explanatory or production components rather than the only preservation format.
A selection matrix
| Primary need | Likely format | Confirm before export |
|---|---|---|
| Original file functionality | Native files plus metadata | Names, paths, hashes, family links, passwords |
| Large-scale legal review | Platform load package | Field map, encoding, dates, text, natives, images |
| Chat and message context | RSMF or structured message format | Participants, time zones, edits, reactions, attachments |
| Targeted mobile review | Portable report or UFDR | Scope, viewer compatibility, included artifacts |
| Curated evidence subset | Tagged export | Selection criteria, context, traceability |
| Easy reading or citation | PDF or images | Metadata loss, searchability, underlying natives |
Ask the receiving team first
The review provider’s import specification should control the package—not a generic assumption about “Relativity format.” Confirm required and optional fields, delimiters, encoding, identifier rules, date format, time zone, native and text paths, image strategy, family handling, message support, and quality-control expectations.
A well-chosen format preserves the information counsel needs and avoids transferring everything a tool happened to parse. The deliverable should be designed, not merely exported.