The Bloomberg administration has recently stepped up enforcement of the artist certification regulations in SoHo and TriBeCa, which it ignored for several years, according to Margaret Baisley, a lawyer opposed to the zoning provision, according to an article by Aline Reynolds in the January 27/February 2 edition of The Villager.

The artist certification for residents of Soho and Noho, established in the early 1970's, when artists began populating the area, requires at least one member of households to be a "creative" artist. They must prove their status in an application to the city's Department of Cultural Affairs.

Residents who apply for artist certification must submit a "professional fine arts" r¿sum¿, two letters of recommendation and other material that demonstrates at least five years of commitment to a particular fine-art genre.

In 2009, the city rejected half the artist-certification applications it received.

The Department of Buildings now denies certificates of occupancy for buildings until each residential unit has an artist certificate. D.O.B. also requires proof of certificate for Soho and Noho loft occupants who apply to renovate their spaces.

Nevertheless, many residents violate the rules, and occupy their lofts illegally, according to various sources.

Baisley said only about 20 to 30 of her Soho clients per year make the effort to comply with the zoning rules, the article said, adding that "about half of them get approved, while the other half get denied. Several others sell their lofts rather than bother hunting down artist tenants to occupy them."

"Are we going to have a protected class of zoning for every profession?" she said. "We don't zone for butchers, bakers or candlestick makers."

Soho and Noho's special zoning allows for residential use in artists' joint work-living quarters. Section 12-10 of the New York City Zoning Resolution refers to individual lofts in Soho and Noho as "arranged and designed for use by...not more than four nonrelated artists," including "adequate working space reserved for [each artist."

Some Soho residents like Sean Sweeney, director of the Soho Alliance, appreciate the law's restrictions. A nonprofit community organization overseeing the neighborhood's quality of life, the Soho Alliance would be influential in any potential effort by the city to rezone Soho and Noho.

Sweeney said the law discourages aggressive landlords from taking over the area and hiking maintenance fees in an effort to evict longtime artist residents.

"It's really an affordable housing question," said Sweeney. "By maintaining the zoning, you're maintaining the ability of artists - of whom there are thousands - to live here."

But, conversely, artist residents who have certification and wish to leave the area are bearing the financial burden of an outdated law, according to Baisley, the article said.

Their lofts, often their biggest investments, are now tricky sells. Buyers are cautioned by lawyers and financial advisers instead to look at other desirable neighborhoods, like Tribeca, to avoid the risk of violating the zoning law.

And since the city began cracking down on illegal residents in the mid-2000's, banks are more wary about giving loans to residents in the area, since they fear that lofts that foreclose would be difficult to resell.