1
seien
(verb) (Indirect Speech (Konjunktiv I)) (wir / sie / Sie)
to be; to exist
In formal texts or speech there is a specific subjunctive verb form for indirect speech. (reporting what someone else has said) This is called the "Konjunktiv i". The third person singular (he/she/it) is formed by taking the stem of the verb (eg; machen --> mach) and then adding on the verb ending 'e', (eg; mach --> er/sie/es mache). The third person plural looks the same as the indicative (normal) conjugation, so often to avoid confusion the "würden + [infinitive]" or Konjunktiv ii form is used.