(Reuters) -The U.S. Securities and Exchange Commission (SEC) has begun an investigation into Illumina (NASDAQ:ILMN)'s $7.1 billion acquisition of cancer detection test maker Grail, the gene sequencing company said in a regulatory filing.
The regulator has requested documents and communications related to the acquisition along with certain statements and disclosures about the "conduct and compensation" of certain members of the companies' management, according to the filing on Thursday.
Shares of the California-based company fell 3.6% in afternoon trading on Friday.
Illumina said it is cooperating with the SEC. An SEC spokesperson said the agency "does not comment on the existence or nonexistence of a possible investigation".
Illumina declined to comment or provide further details on the SEC investigation.
The gene-sequencing machine maker had repurchased Grail in 2021, despite opposition from U.S. and European antitrust regulators, a decision that prompted investor Carl Icahn to pursue a proxy fight at Illumina, arguing Grail should be divested as it had cost investors billions of dollars.
Illumina was fined 432 million euros ($476 million) by the EU last month for closing the deal before approval by European antitrust regulators.