Medical Properties Trust filed suit in federal court against Viceroy Research, alleging that the company repeatedly published baseless allegations to drive MPT's stock price down. The lawsuit seeks permanent injunctive relief and unspecified compensatory and punitive damages from Viceroy.

“The chorus of false and intentionally deceptive claims from Viceroy Research and others who stand to benefit from declines in MPT’s stock price has grown so loud that we can no longer sit by idly,” the company said in a letter to its shareholders on Thursday.

MPT stock has indeed dropped recently. From a recent high of nearly $14 per share in January, it has fallen to about $8 per share Friday. MPT shares have dropped nearly 62% compared with a year ago, when they traded for more than $21 per share.

Late in January, Viceroy Research, which calls itself an investigative financial research group, released a report alleging that MPT “engaged in billions of dollars of uncommercial transactions with its tenants and their management teams in order to mask a pervasive revenue round-robin scheme and/or theft.”

The suit alleges that Viceroy attacks companies it has a short position in, with the aim of driving down their stock price, and that its latest target is MPT.

“The playbook for these attacks is simple,” the suit alleges. “Take a short position in a stock or partner with someone who has one, publish false 'research' critical of the target company, amplify the false claims on social media, and then reap a profit.”

The suit noted that MPT’s stock price is down since the attacks, and that a potential counterparty pulled away from a commercial transaction recently. Also, it said MPT has had to increase physical security at its Birmingham, Alabama, headquarters.

The suit acknowledged that short selling is lawful, even by an entity that has been critical of the target of the short selling. Even so, it alleges that Viceroy's behavior are beyond the pale, asserting that it has been “spreading malicious falsehoods about MPT.”

Viceroy did not immediately respond to a request for comment from Bisnow Friday.