What it is
When a survey number's parcel is later split, through partition among heirs, a sale of part of the land, or a change in use, each resulting piece is not given a brand-new survey number. Instead it keeps the parent number and adds a subdivision suffix after a slash, so one original survey number can become /1, /2, /3 and so on as splits accumulate. The subdivision is what narrows a record down to the exact fragment you are dealing with, not just the general block.
Why it matters when you buy
Two neighbours can hold patta for the same survey number but different subdivisions, and their boundaries, extents and even soil classification (nanjai or punjai) can differ. Quoting only the survey number when you check records risks pulling up a neighbour's history instead of the seller's. Always confirm the subdivision on the patta, the FMB sketch and the draft sale deed match exactly, and ask whether the subdivision was created through a registered partition or an unregistered family arrangement, since that affects how clean the title is.
Where you find it
It appears immediately after the survey number on the patta-chitta, the FMB sketch, and any subdivision-specific A-register extract, always separated by a slash, for example 145/2. The village revenue records office maintains the map showing exactly how a survey number's subdivisions divide its total extent, and can tell you, on request, how and when a particular subdivision was created.