  We present the first model-independent measurement of the absolute branching
fraction of the Lambda_c+ -> p K- pi+ decay using a data sample of 978 fb^-1
collected with the Belle detector at the KEKB asymmetric-energy e+e- collider.
The number of Lambda_c+ baryons is determined by reconstructing the recoiling
D(*)- anti-p pi+ system in events of the type e+e- -> D(*)- anti-p pi+
Lambda_c+. The branching fraction is measured to be Br(Lambda_c+ -> p K- pi+) =
(6.84 +- 0.24^{+0.21}_{-0.27})%, where the first and second uncertainties are
statistical and systematic, respectively.
