Sentences with plural definites like ‘the circles’ are usually interpreted akin to universally quantified sentences (maximal reading). In some circumstances, however, they also allow for non-maximal readings, i.e imprecise readings that allow for exceptions. We report two mouse-tracking experiments that investigate the online derivation of these non-maximal in- terpretations of plural definites. Our results show that non- maximal readings are harder to process than maximal interpre- tations. This difficulty seems to be associated to hesitation in the decision-process rather than to a truly two-step derivation. Interestingly, we also find that experimental setup plays an im- portant role in the availability and difficulty linked to these readings.