2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/222738We define sutured Heegaard diagrams for null-homologous knots in 3-manifolds. These diagrams are useful for computing the knot Floer homology at the top filtration level. As an application, we give a formula for the knot Floer homology of a Murasugi sum. Our result echoes Gabai's earlier works. We also show that for so-called 'semifibred' satellite knots, the top filtration term of the knot Floer homology is isomorphic to the counterpart of the companion.This is the version published by Algebraic & Geometric Topology on 2 April 2006Geometric Topology57M27, 57R58, 53D40text