Abstract: A wiring circuit board includes an insulating layer having a via penetrating in a thickness direction, a first conductive layer disposed on a one-side surface in the thickness direction of the insulating layer, a second conductive layer disposed on the other-side surface in the thickness direction of the insulating layer, and a conductive portion disposed on an inner peripheral surface of the via and electrically connecting the first and second conductive layers. Length L of 1 µm-10 µm inclusive, is measured by: drawing a segment joining first and second connection points from respectively, the one-side surface to the other-side surface in the thickness direction of the insulating layer and the inner peripheral surface in the cross-sectional view; identifying an outermost position farthest outward from the segment on the inner peripheral surface in the cross-sectional view; and measuring the length as the shortest distance from the segment to the outermost position.

Abstract: A wiring circuit board includes a porous insulating layer, and a first conductive layer sequentially toward one side in the thickness direction. The first conductive layer includes a first signal wire and first ground wires. Each of the first ground wires is thicker than the first signal wire.

Abstract: A film for a metal layer laminate board and a metal layer laminate board have excellent stiffness, while capable of suppressing fluctuation of a dielectric constant before and after pressing. The film for a metal layer laminate board includes a porous resin layer having a tensile elastic modulus at 25° C. of 800 MPa or more and 2000 MPa or less.