Around 20 cases of answer-sheet mismatch were detected during the CBSE's first large-scale implementation of its digital On-Screen Marking (OSM) system this year, government sources told NDTV, after students discovered that scanned copies uploaded on the board's portal belonged to other candidates.
The issue came to light during the re-evaluation process, when students were given access to digitised copies of their board exam answer sheets following the declaration of the Class 10 and Class 12 results earlier this month.
"There are around 20 cases where answer sheets got mixed up during the scanning process. Students identified the problem after accessing the uploaded copies," a senior official said.
One of the cases that drew widespread attention involved Class 12 student Vedant Shrivastava, who alleged on social media that the Physics answer sheet shared by the board during the re-evaluation process did not belong to him.
"When Vedant checked the uploaded copy, he realised it belonged to someone else. There was another student, Sanjana, who also reported a similar issue," the official said.
Screenshots and videos posted by students on social media quickly gained traction, with several users questioning the reliability of the CBSE's new digital evaluation framework and demanding greater transparency in the process.
CBSE later contacted the affected students and shared the correct answer sheets. The board has maintained that complaints related to mismatched answer sheets and other re-evaluation concerns are being addressed on a "top priority" basis.
The answer-sheet mismatch cases emerged alongside broader operational challenges during the board's large-scale digitisation exercise this year.
According to sources, nearly 98 lakh answer sheets, amounting to almost 40 crore pages, were scanned under the OSM system introduced for the 2026 evaluation cycle.
Officials said around 68,000 answer sheets were initially flagged because of poor scan quality and had to be rescanned.
"Even after rescanning, a little over 13,000 answer sheets could not achieve the required level of readability," sources said, adding that these copies were eventually shifted to manual evaluation.
The On-Screen Marking system was introduced by CBSE as part of a broader push towards digitising the examination and evaluation process. Under the system, answer sheets are scanned and uploaded digitally, allowing evaluators to assess copies remotely instead of physically handling bundles of papers at designated centres.
Also Read: "OSM Is The Future": Govt Defends CBSE's Digital Evaluation Amid Portal Hacking, Answer Sheet Row
Officials say the system was designed to reduce logistical delays, speed up evaluation and minimise the risk of physical damage to or loss of answer sheets. Several state boards and competitive examination agencies have also gradually adopted digital evaluation systems in recent years.
However, education experts point out that large-scale digitisation exercises involving crores of scanned pages require robust quality-control mechanisms, particularly because even minor scanning or indexing errors can affect students during re-evaluation and verification processes.
The latest disclosures come amid increasing scrutiny of the CBSE's transition to digital evaluation after multiple students reported blurred pages, technical glitches and discrepancies in uploaded answer sheets following the declaration of board results.
