This study analyzes the production efficiency gains in terms of technology transfer and labour productivity changes caused by diverse degrees of foreign ownership using a sample of 4,056 manufacturing firms operating in Greece in 1997. Departures from normality of labour productivity and its logarithm led to the adoption of the robust technique of quantile regression. Interesting results include a positive effect on labour productivity of foreign ownership, which stems exclusively from full and majority owned affiliates and becomes significant only in the middle quantiles. Productivity spillovers benefiting local firms are also differentiated, with minority holdings exercising a stronger effect in most quantiles.