遡そ及きゅう

noun, noun or participle which takes 'suru', intransitive verb

retroactivity; retroaction; being retroactive (to)

Used in legal, administrative, or formal contexts to describe something that takes effect from a past date. Often appears as 遡及する (to be retroactive) or 遡及して (retroactively).

• 新あたらしい法ほう律りつは公こう布ふの日ひに遡そ及きゅうして適てき用ようされる。

  The new law is applied retroactively to the date of its promulgation.

• この規き定ていは過か去この取とり引ひきに遡そ及きゅうしない。

  This provision does not apply retroactively to past transactions.