The phrase "retroactive application" means applying a law, rule, or decision to past events or situations, even though it was made or enacted after those events occurred. Full definition
As Dennis Crouch pointed out over at Patently - O, the release of an informally proposed amendment to the current patent reform bill that would set April 24 as a cutoff date for retroactive application of fee shifting provisions set off a surge of patent case filings just before the deadline. (lexmachina.com)
These amendments came into force on January 1, 2018, with retroactive application to April 29, 2014. (mathewsdinsdale.com)
In considering that claim, the court resorted to the principles set out in a well - known Supreme Court of Canada decision in D.B.S. v. S.R.G., where the court set out the factors that family courts should take into account in detailing with such retroactive applications. (familyllb.com)