We present continuum high resolution Submillimeter Array ( SMA ) observations of the transition disk object RX J1633.9-2442 , which is located in the Ophiuchus molecular cloud and has recently been identified as a likely site of ongoing giant planet formation . The observations were taken at 340 GHz ( 880 \mu m ) with the SMA in its most extended configuration , resulting in an angular resolution of 0.3 ^ { \prime \prime } ( 35 AU at the distance of the target ) . We find that the disk is highly inclined ( i \sim 50 deg ) and has an inner cavity \sim 25 AU in radius , which is clearly resolved by our observations . We simultaneously model the entire optical to millimeter wavelength spectral energy distribution ( SED ) and SMA visibilities of RX J1633.9-2442 in order to constrain the structure of its disk . We find that an empty cavity \sim 25 AU in radius is inconsistent with the excess emission observed at 12 , 22 , and 24 \mu m. Instead , the mid-IR excess can be modeled by either a narrow , optically thick ring at \sim 10 AU or an optically thin region extending from \sim 7 AU to \sim 25 AU . The inner disk ( r \lesssim 5 AU ) is mostly depleted of small dust grains as attested by the lack of detectable near-IR excess . We also present deep Keck aperture masking observations in the near-IR , which rule out the presence of a companion up to 500 times fainter than the primary star ( in K -band ) for projected separations in the 5-20 AU range . We argue that the complex structure of the RX J1633.9-2442 disk is best explained by multiple planets embedded within the disk . We also suggest that the properties and incidence of objects such as RX J1633.9-2442 , T Cha , and LkCa 15 ( and those of the companions recently identified to these two latter objects ) are most consistent with the runaway gas accretion phase of the core accretion model , when giant planets gain their envelopes and suddenly become massive enough to open wide gaps in the disk .