Securities regulators are looking into the joint bid by Valeant Pharmaceuticals and activist investor Bill Ackman for Allergan, Dow Jones reported on Thursday, citing sources familiar with the matter.
The SEC is looking into whether the offer broke any insider trading laws, according to the report.
Dow Jones also reported that the probe was a civil one and at an early stage.
"We welcome the SEC's review of the facts," Ackman's Pershing Square said in a lengthy statement defending its actions.
"We are confident that the trading was completely lawful, as our reply to Allergan's frivolous lawsuit will make clear," Valeant said in a statement.
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