  The gas and solid-state C/O ratios provide context to potentially link the
atmospheric composition of planets to that of the natal disk. We provide a
synthesis of extant estimates of the gaseous C/O and C/H ratios in
planet-forming disks obtained primarily through analysis of Atacama Large
Millimeter Array observations. These estimates are compared to atmospheric
abundances of wide separation (> 10 au) gas giants. The resolved disk gas C/O
ratios, from seven systems, generally exhibit C/O > 1 with sub-solar, or
depleted, carbon content. In contrast, wide separation gas giants have
atmospheric C/O ratios that cluster near or slightly above the presumed stellar
value with a range of elemental C/H. From the existing disk composition, we
infer that the solid-state mm/cm-sized pebbles have a total C/O ratio (solid
cores and ices) that is solar (stellar) in content. We explore simple models
that reconstruct the exoplanet atmospheric composition from the disk, while
accounting for silicate cloud formation in the planet atmosphere. If wide
separate planets formed via the core-accretion mechanism, they must acquire
their metals from pebble or planetesimal accretion. Further, the dispersion in
giant planet C/H content is best matched by a disk composition with modest and
variable factors of carbon depletion. An origin of the wide separation gas
giants via gravitational instability cannot be ruled out as stellar C/O ratios
should natively form in this scenario. However, the variation in planet
metallicity with a stellar C/O ratio potentially presents challenges to these
models.
