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The prospects of future galaxy surveys for non-Gaussianity measurements callfor the development of robust techniques for computing the bispectrum ofprimordial cosmological perturbations. In this paper, we propose a novelapproach to the calculation of the squeezed bispectrum in multiple-fieldinflation. With use of the $\delta N$ formalism, our framework sheds new lighton the recently pointed out difference between the squeezed bispectrum forglobal observers and that for local observers, while allowing one to calculateboth. For local observers in particular, the squeezed bispectrum is found tovanish in single-field inflation. Furthermore, our framework allows one to gobeyond the near-equilateral ("small hierarchy") limit, and to automaticallyinclude intrinsic non-Gaussianities that do not need to be calculatedseparately. The explicit computational programme of our method is given andillustrated with a few examples.

Squeezed Bispectrum in the $\delta N$ Formalism: Local Observer Effect in Field Space