When a document is uploaded to Sumsub, it passes through a series of automated checks. One of these checks utilizes the optical character recognition (OCR) technology to detect the following:

All pages and sides of the document are uploaded.
Document number and name fields are present, clearly visible, and can be recognized.
Document image is not a screenshot.
Image has not been cropped.
Document is not considered expired or issued in the forbidden territory in accordance with the customer settings.
Document image has not been rejected during previous iterations.
Photo in the document contains the human face.
In case the fastfail check is not passed, the system notifies the applicant and sends a document resubmission request immediately after they upload the photo of the document.

Error rejection tags

Errors do not let applicants proceed with verification using the presented document.

Tag	Description
`forbiddenDocument`	Unsupported or unacceptable type/country of the document.
`differentDocTypeOrCountry`	Document type or country do not match the ones specified by the applicant or recognized by the system.
`missingImportantInfo`	Some of the required document data is missing or cannot be read.
`dataNotReadable`	Data on the image is missing or cannot be read.
`expiredDoc`	Document is expired.
`documentWayTooMuchOutside`	Some parts of the document are cropped.
`noIdDocFacePhoto`	Face is not clearly visible on the document.
`selfieFaceBadQuality`	Face is not clearly visible on the selfie.
`screenRecapture`	Provided image might be a photo or a screenshot.
`screenshot`	Provided image is a screenshot.
`sameSides`	Image of the same side of the document was uploaded as front and back sides.
`shouldBeMrzDocument`	Provided document type should have an MRZ, but there is no readable MRZ on the image.
`shouldBeDoubleSided`	Sides of the document should be provided.
`shouldBeDoublePaged`	Full double-page photo of the document (usually, two main passport pages) is required.
`documentDeclinedBefore`	Same image was uploaded earlier by the same applicant and declined by the system.
`mrzNotReadable`	We could not extract the MRZ code from the uploaded document. This may happen due to a variety of reasons, such as poor image quality or some corners of the document are missing, which may include the MRZ area.
`docExpiresSoon`	The submitted document is about to expire in N months. This is defined by the Minimum residual validity of ID document setting in the Dashboard.
`missingDob`	The document does not contain the owner's date of birth.
`incompleteDob`	The document does not contain the full date of birth (day, month, and year).

Warning rejection tags

Warnings let applicants proceed with verification after retaking the document photo and providing missing information.

Tag	Description
`badSelfie`	Face or the photo in the document is not clearly visible.
`dataReadability`	Information in the document cannot be read.
`inconsistentDocument`	Uploaded photos do not belong to the same document.
`maybeExpiredDoc`	Document may be expired.
`documentTooMuchOutside`	Document is not fully in the frame.