Retrospective amendment validates past application of the specified tax valuation rule, treating actions during the period as effective. Retrospective amendment modifies rule 2A of the Service Tax (Determination of Value) Rules, 2006 as specified in the Sixth Schedule, deeming the rule amended for the listed periods and validating any action taken during those periods as always having been valid and effective, notwithstanding judgments or orders; the Central Government is declared to have retrospective rulemaking power for this purpose, and no act or omission is to be rendered punishable by reason of this section if it would not have been punishable otherwise.