Hospital landlord Medical Properties Trust (MPT) has taken legal action to block a books-and-records demand by short seller activist Viceroy Research.

Viceroy made the demand as part of a short campaign alleging MPT failed to disclose “round-tripping” transactions between its off-balance sheet investment vehicles and the beneficial owner of its fourth largest tenant.

In a court filing made public by the short seller, MPT opposed the request on grounds that it goes beyond the scope of discovery as provided under applicable law.

MPT also argued that the request covers information restricted by attorney-client privilege, work-product immunity and business strategy immunity.

Viceroy issued a short report on September 26. Despite the report, MPT’s stock has remained relatively stable, closing at $5.36 per share Tuesday, up 4.5%.