Community Health Systems has received yet another federal subpoena related to its emergency room admission practices — this time from the Securities and Exchange Commission.

In an 8-K filed Wednesday afternoon, the Franklin-based hospital company said it received a subpoena from the regulatory agency on May 13 requesting documents “related to or requested in connection with the various inquiries, lawsuits and investigations” regarding the emergency room admission and observation practices at CHS’ hospitals.

That document pile, at this point, should be quite large. In the past six weeks the company has been hit with a lawsuit from former acquisition target Tenet Healthcare, subpoenas from the Office of the Inspector General at the U.S. Department of Health and Human Services and U.S. Department of Justice, and several class action suits — all related to this ER admissions issue. The Texas Attorney General’s office has been investigating the ER practices at CHS’18 facilities in that state since last November.

The SEC also wants the documents CHS relied upon in responding to Tenet’s lawsuit and other communications related to that litigation. Likely among those documents are materials related to CHS’ April 28 investor call, in which the company’s management spent considerable time refuting Tenet’s claims.

Tenet filed an amended lawsuit against CHS on Monday — about a week after CHS ended its acquisition pursuit — seeking damages for the money it spent investigating and suing CHS (Ticker: CYH). In its 8-K, CHS acknowledges the amended complaint it says “expands on the unverified facts” in Tenet’s first suit.

“We believe the allegations are without merit and will vigorously defend this suit,” the filing reads.