A federal magistrate judge in San Francisco is considering whether to allow California's largest medical marijuana dispensary to continue to operate in Oakland while that city battles a federal effort to shut down the facility.

U.S. Magistrate Judge Maria-Elena James heard arguments Thursday on motions in two related lawsuits concerning the Harborside Health Center but took the cases under submission and will rule at a later date.

The dispute stems from a law enforcement effort in which federal prosecutors throughout California last year began filing forfeiture lawsuits against the landlords of medical marijuana dispensaries that prosecutors considered to be large-scale commercial enterprises.

While California's 1996 medical marijuana law allows seriously ill patients to use the herb for health purposes, federal laws criminalizing marijuana do not recognize the state law.

Harborside's Oakland facility and a smaller subsidiary in San Jose were targeted in federal lawsuits filed in July by U.S. Attorney Melinda Haag of San Francisco, seeking forfeiture of the landlords' property on the ground that the buildings were used for illegal activities.

At the time, Haag called Harborside a "superstore" and said, "The larger the operation, the greater the likelihood that there will be abuse of the state's medical marijuana laws, and marijuana in the hands of individuals who do not have a demonstrated medical need."

In October, Oakland responded with a lawsuit seeking to block the forfeiture bid.

The city contends that since Harborside has operated in compliance with state and city laws since 2006 without federal interference, the five-year statute of limitations for a civil forfeiture lawsuit has passed.

Meanwhile, Harborside's Oakland landlord, Ana Chretien, has asked James to order Harborside to stop growing, possessing or selling marijuana on her property.

Her lawyers have argued she needs the order to prevent the possible "profound harm" of forfeiture of her property.

Oakland's lawyers have filed an opposing motion asking James to halt proceedings on both Chretien's request and the forfeiture lawsuit until the city's own lawsuit is resolved.

James heard arguments Thursday on both those motions as well as a third request in which Harborside's San Jose landlord is also asking for an order blocking marijuana activities. She has no deadline for ruling.

Outside of court, Oakland City Attorney Barbara Parker said, "We would like the federal government to stop this tragic waste of resources to shut down legitimate regulations in conformance with California law and to deny patients access to marijuana."

"This is a system that's in place and it's working," Parker said.

Parker said closing regulated dispensaries would create a black market that would divert police resources from what she called Oakland's "true public safety crisis -- homicides and gang violence."

Harborside says its two facilities serve about 115,000 registered patients.

Executive Director Steve DeAngelo said he believes the Oakland dispensary is the state's largest.

He said Harborside is still operating as a dispensary and will continue to do unless ordered by a court to stop.

"We have no intention of doing anything other than continuing to serve our patents," DeAngelo said after the hearing.

Jack Gillund, a spokesman for Haag, said because the case is ongoing, she has no comment other than her statement in July.