Usually yes, but the integration question people ask — does it connect to our VDR? — is the easy half. The hard half is what happens to the documents that do get through: scanned agreements with no text layer, files past a length ceiling, formats nobody supports. These fail quietly, produce zero findings, and zero findings is indistinguishable from a clean document.
Three integration paths, in order of how often they matter
| Path | Works when | Watch for |
|---|---|---|
| Direct API to the VDR | Major providers with published APIs | Permission model — does it see what your user sees? |
| Bulk export and upload | Always. The universal fallback | Folder structure and metadata loss |
| Watched folder / sync | Incremental disclosure over weeks | Whether re-uploads trigger reprocessing of everything |
The unglamorous middle row is the one that actually carries most deployments, and it is worth designing around rather than treating as a stopgap. Bulk export always works, needs no vendor cooperation from your VDR, and — importantly — sidesteps the permission-model question entirely, because you control exactly what leaves.
Direct API integration is genuinely convenient and introduces a specific risk worth naming: an integration authenticated with broad credentials can pull documents a given user should not see. If you run clean-team arrangements, ask precisely whose permissions the integration inherits.
The real problem: what survives extraction
“Legacy” in practice rarely means an old VDR. It means old documents, and four categories fail routinely:
Scanned paper with no text layer
The oldest agreements in a data room are often the most interesting — the original supply contract, the founding shareholder agreement, the lease with the unusual assignment clause. They are also the most likely to be a photograph of a page.
OCR handles clean scans well and degrades on faxes, stamps, handwriting, marginalia and poor contrast. Ask two questions: does the system OCR at all, and does it report OCR confidence or simply proceed?
Documents past a length ceiling
Every system has one. The credit agreement is both the longest document in the room and the one that matters most, which makes silent truncation expensive in a very specific way.
Spreadsheets and structured files
Frequently treated as unsupported and dropped. Financial schedules and contract registers often carry material information.
Password-protected, corrupted, or proprietary formats
Common in older rooms, and usually skipped without comment.
The requirement that makes legacy material safe
Not better OCR — coverage reporting as a first-class output. Documents submitted, processed in full, partially processed, failed, with reasons.
Then reconcile it against the room before reading a single finding. Two minutes for an entire data room, and it converts the most dangerous failure mode in this category from invisible to obvious.
A useful test during evaluation: submit a deliberately broken set — a scan, an over-length agreement, a spreadsheet, a password-protected file — and see whether the tool reports four failures or simply returns findings on the documents it could read. Vendors do not put this in demos.
Metadata loss, which is subtler than it sounds
Bulk export flattens things. Folder structure, upload dates, document relationships and version history frequently do not survive, and some of that is analytically relevant:
- Which amendment belongs to which base agreement. Without the relationship, a fourth amendment is just another document, and the obligation it modifies is assessed against a superseded original.
- Upload timing. Documents disclosed late in a process are disproportionately the ones a seller was slow to produce. That signal is worth preserving.
- Folder taxonomy. The seller's own categorisation carries information about what they consider related.
Ask whether the tool can ingest a manifest alongside the documents, and whether it links amendments to base agreements — and, more valuably, whether it flags a base agreement whose referenced amendments are absent from the room. That is a disclosure-gap detector and it is worth more than most finding types.
Incremental disclosure
Data rooms fill over weeks, so re-processing behaviour matters commercially. Ask whether the system can process only new and amended documents, or whether every batch means reprocessing the whole room.
Without a delta mode, teams stop re-running as the room grows — which means the documents disclosed latest, the ones most likely to hold surprises, get screened least.
What not to fix
Two things teams over-invest in:
Deep VDR integration before proving value. Bulk export works on deal one. Build the integration after you know the tool earns its place, not as a precondition for finding out.
Perfect format coverage. You do not need every file type processed. You need to know which were not, so those get human eyes. A tool that handles 88% of formats and reports the other 12% precisely is safer than one that handles 96% silently.
The verification angle
Legacy documents raise verification cost specifically, because a finding extracted from an OCR'd scan needs checking against an image rather than searchable text.
This makes quoted source text more valuable here, not less. Grounded commercial legal AI has been measured hallucinating between 17% and 33% of the time in an adjacent task, with providers' hallucination-free claims judged overstated[1] — and OCR adds its own error layer on top. A finding that reproduces the source sentence, with a page reference into the original image, is checkable. One that merely asserts a conclusion about a scanned document is not.
Bottom line
Connectivity is rarely the blocker; bulk export works everywhere and avoids the permission questions API integration raises. The real risk is the legacy document — the scan, the over-length agreement, the unsupported format — failing silently and reading as clean.
So require coverage reporting, reconcile counts before reading findings, ask about amendment linking and absence detection, and check for a delta mode. Then route everything that failed to a human, which is a perfectly good answer as long as you know what failed.
Sources
- Magesh, V., Surani, F., Dahl, M., Suzgun, M., Manning, C. D., & Ho, D. E. Hallucination-Free? Assessing the Reliability of Leading AI Legal Research Tools. arXiv:2405.20362; Journal of Empirical Legal Studies (2025). See the scoping note above. arxiv.org/abs/2405.20362
We publish no OCR or format-coverage percentages because we are aware of no independent measurement. We cite only sources we have retrieved and read — see our methodology.