"A judgment of the Court of Justice of 29 March in an unrelated case clarified the legal rules as to limitation periods for the imposition of fines by the (European) Commission," the EU executive said in a statement.
"As a result of that clarification, it was clear that the Commission decision of 2009 was incorrect in that the limitation period on these two companies had expired."
The regulator said it had repealed Ciba's €68.4m (£61.8m) fine and Elementis' €23.4m penalty.
The British firm had been fined almost €32.6m in total, part of which was a joint penalty with Netherlands-based AkzoNobel, a Commission spokeswoman said.
Elementis will not have to pay it share of this fine either, but the penalty against AkzoNobel stands.
Price-fixing fines were imposed on 24 chemicals companies in November 2009. Penalties for the other 22 firms remain in place.
Elementis had earlier on Monday announced the Commission's decision.