  We investigate whether certain extra-solar multi-planet systems
simultaneously follow the scaling and spacing rules of the
angular-momentum-deficit model. The masses and semi-major axes of exoplanets in
ten multi-planet systems are considered. It is found that GJ 667C, HD 215152,
HD 40307, and Kepler-79 systems are currently close to configurations of the
angular-momentum-deficit model. In a gas-poor scenario, GJ 3293, HD 141399, and
HD 34445 systems are those which had a configuration of the
angular-momentum-deficit model in the past and get scattered away due to post
gaseous effects. In addition, no matter in gas-free or gas-poor scenario, 55
Cnc, GJ 876, and WASP-47 systems do not follow the angular-momentum-deficit
model. Therefore, our results reveal important formation histories of these
multi-planet systems.
