The dispute arose in July 2006 when EPA inspectors conducted an inspection at Mayo's Boston offices and determined that lead paint disclosure had not been provided to tenants prior to executing lease contracts, which violates the Toxic and Federal Disclosure Rule. The properties in question range five communities in Massachusetts, many of which were constructed before 1978 and are subject to the lead paint Disclosure Rule, according to an EPA release.

The Disclosure Rule gives tenants adequate information about the risks associated with lead paint in particular rental units and related common areas so that they may consider the risks prior to agreeing to obligations under a lease contract. It was determined that Mayo failed to comply with the Disclosure Rule in regard to lead-based paint on window replacements which were in units that were then rented.

Taran Grigsby, general counsel for Mayo, explains, "When you own a building that was built before 1978, and you rent an apartment in that building you are required to have the renter sign what is called a lead paint disclosure form. And it's a form where a landlord discloses if the lead paint was abated, encapsulated and how are you complying with the lead paint law." The lead paint report is then supposed to be attached to the back. That's the violation that the EPA is alleging, that we had failed to have a resident sign the disclosure form."