We present the identification of WISE J135501.90 - 825838.9 as a spectral binary system with a slight possibility of planetary-mass components in the 130 - 200 Myr AB Doradus moving group .
Peculiarities in the near-infrared spectrum of this source suggest it to be a blended-light binary with L6.0 \pm 1.0 and T3.0 \pm 1.8 or L7.0 \pm 0.6 and T7.5 \pm 0.4 components .
Its proper motion and radial velocity as a combined-light source yield a high membership probability for AB Doradus .
While the young L6+T3 case is underluminous in a color-magnitude diagram at the AB Doradus kinematic distance , the young L7+T7.5 case could be viable .
Gravity-sensitive indicators are more consistent with a field-age binary .
If confirmed as a young object , member of AB Doradus , we estimate masses of 11 \pm 1 M _ { \mathrm { Jup } } and 9 \pm 1 M _ { \mathrm { Jup } } with both component masses below the Deuterium burning mass limit .
Otherwise , we find masses of 72 ^ { +4 } _ { -5 } M _ { \mathrm { Jup } } and 61 ^ { +6 } _ { -8 } M _ { \mathrm { Jup } } for the field L6+T3 case and 70 ^ { +2 } _ { -4 } M _ { \mathrm { Jup } } and 42 ^ { +5 } _ { -6 } M _ { \mathrm { Jup } } for the field L7+T7.5 case .
Our identification of WISE J135501.90 - 825838.9 as a candidate young spectral binary introduces a new technique for detecting and characterizing planetary-mass companions to young brown dwarfs .