OPT file
An OPT file is the page-level image load file in a document production. Each comma-separated row lists one page's Bates number, the production volume, the path to its TIFF or PDF image, and a Y flag on the first page of every document so the receiving platform knows where each document starts and how many pages it has.
Also called: Opticon file · image load file · Opticon load file
Updated September 6, 2026
How does an OPT file work?
Where the DAT file describes documents, the OPT file describes pages. A document imaged to four TIFF pages produces four OPT rows. The Y in the fourth field of the first row marks the document boundary; the receiving platform reads rows until the next Y to assemble the document. Paths are relative to the root of the production volume so the set can be loaded from any location.
Natively produced documents typically get a single OPT row pointing at their slip sheet, the placeholder image bearing the Bates number, while the native file itself is referenced from the DAT.
What does an OPT file look like in practice?
SMITH-000148,VOL001,\IMAGES\001\SMITH-000148.tif,Y,,,4
SMITH-000149,VOL001,\IMAGES\001\SMITH-000149.tif,,,,
SMITH-000150,VOL001,\IMAGES\001\SMITH-000150.tif,,,,
SMITH-000151,VOL001,\IMAGES\001\SMITH-000151.tif,,,,
SMITH-000152,VOL001,\IMAGES\001\SMITH-000152.tif,Y,,,1Rows one to four are one four-page document. Row five is the placeholder for a natively produced attachment.
Reconciling OPT rows against image count and Bates range is one of the pre-send checks on the production checklist.
How does an OPT file show up on an eDiscovery invoice?
OPT generation is part of the production export and is priced within the production fee. The cost driver behind it is imaging: converting natives to TIFF is commonly billed per page or per gigabyte as a separate format conversion or TIFFing line, which is why a hybrid protocol that keeps spreadsheets and presentations native reduces both risk and cost. See the format risk planner.
Sources
- EDRM production guidance on image load files.
- The Sedona Conference Glossary, “Opticon.”
Related terms
eDiscovery at one flat monthly rate
$3,250 a month on a 12-month agreement. No per-user fees and no per-GB hosting charges.
Common questions
What are the seven fields in an OPT file?
Bates number, volume name, image path, document-break flag (Y on the first page of a document, blank otherwise), folder-break flag, box-break flag, and page count on the first page of each document. Only the first four are commonly populated.
What is the difference between OPT and LFP files?
Both are image load files. OPT is the Opticon format, comma-separated with seven fields. LFP is the IPRO format, with a different structure that includes an explicit page offset. Most platforms read both; the ESI protocol should say which to deliver.
Why does my OPT file not load?
Usually a path problem: the image paths in the file do not match the folder structure delivered, or use absolute paths from the producing party's system. The second most common cause is a Bates number in the OPT that does not appear in the DAT, so the platform cannot pair the page with a document.