Refers to including a key piece of information in a large amount of other less relevant information, in hope that the recipient will not have time to consider all the material and not spot the relevance of the key information. A form of ‘burying the lede.’
It is sometimes alleged that very large information disclosure statements to the USPTO may bury key references in a pile of dozens or even hundreds of others – seeking to ensure that the prior art is included in the cited references, but not spotted by the patent examiner, rendering that art harder to use for invalidation purposes.