dürften

first/third-person plural subjunctive II of dürfen

(auxiliary, preterite-present) to be allowed (to do something); to be permitted (to do something); may
(intransitive, participle, past, preterite-present, transitive) to be allowed or permitted to do something implied or previously stated; may
(auxiliary, preterite-present, subjunctive-ii) expresses a prediction with mild doubt, that something is estimated or probable
(colloquial, preterite-present) must, to have [got] to, gotta
(obsolete, preterite-present, transitive, with-genitive) to need, to require