Cubist Pharmaceuticals disclosed this week in a regulatory filing with the Securities and Exchange Commission that it is under investigation by the SEC and Department of Justice for potential violations of the Foreign Corrupt Practices Act.

In a Form 8-K, dated Aug. 11, Cubist said the FCPA allegations concern "a potentially improper payment to a research laboratory" and an "attempted share grant” in 2011 by Optimer Pharmaceuticals, a biopharmaceutical company that Cubist acquired last year.

Cubist did not provide any further details on the investigation. In March 2013, however, the company disclosed in a regulatory filing that the company’s CEO and its chief compliance officer resigned at the request of independent board members after a year-long internal investigation uncovered potential violations of the FCPA.

Specifically, the investigation revealed that an attempted share grant made in 2011 to Michael Chang, and a potentially improper payment of $300,000 made to a research laboratory that same year, may have violated the FCPA. In response, the board removed Michael Chang as chairman.

In its latest filing, Cubist said it is “continuing to cooperate with the investigations” by the SEC and the Justice Department. It added that it does not have “any amounts accrued related to potential penalties or other remedies related to these matters as of June 30, 2014, and cannot estimate a reasonably possible range of loss.”