By Adam Leitman Bailey

Q. In condos and co-ops that have mail distributed into open slots by building staff, what regulations, if any, govern the handling of non-Postal Service mail? Do house rules alone dictate whether residents can leave noncommercial messages for other residents? Can quantity or frequency be restricted? Does it matter whether messages are loose flyers or in sealed, addressed envelopes? Do free-speech laws allow messages to be slipped under apartment doors? . . . Larry Simms, Manhattan.

A. Adam Leitman Bailey, a Manhattan real estate lawyer, said that federal law and New York State’s Housing Maintenance Code require all multiple dwellings, including co-ops and condos, to arrange for mail to be delivered properly. Usually, Mr. Bailey said, that is done by using locked mailboxes that can be accessed only by tenants and postal workers. With that system, he said, postal regulations permit only mail that is postmarked to be placed in the boxes.

But some buildings use the system described by the writer. And whether it can be used for private purposes is up to building management.

Mr. Bailey said that while many co-ops and condos prohibit or restrict distribution of commercial messages, most do not prohibit noncommercial messages, nor do they define quantity, frequency or packaging. But, he said, ‘’the business judgment rule allows a co-op board to exercise extensive powers, including the ability to include such provisions in the bylaws or house rules.’’

He added while free-speech laws prohibit public entities from denying individuals the right to make their views known, such laws do not apply to private entities like co-ops and condos. So, he said, ‘’co-op and condo boards can prohibit the slipping of messages under apartment doors if the board believes it is acting in the best interests of the building.’’