Drone startup founders and CEOs are not happy about a bill in the California state legislature that would place new restrictions on unmanned aerial vehicle flight in the state.

California Senate Bill 142 would prohibit flight within airspace up to 350 feet above private property unless the property owners in question gave “express permission” for the vehicle to hover over the area. As Re/code put it, delivering a package by drone to a location would be difficult if a neighboring property lay in a no-fly zone.

Drone advocates say the bill is an ironic development for the home state of Silicon Valley, where a large number of drone companies are based and where innovation in the emerging industry is largely centered. The bill would pretty much ground the industry in the state, they say--and it could force some companies to leave or at least take their services elsewhere.

The issues.

Mike Winn, CEO of San Francisco-based DroneDeploy, which makes drone software, tells Inc. the bill is too broad. “It doesn’t meaningfully address privacy issues,” which is one stated reason behind the proposed requirement of permission, he says. At the same time, the bill “arbitrarily (reduces) the ways drones can create value.”

“We’d encourage California and other law makers to enforce existing laws that prevent trespassing and provide remedies for privacy violations and focus on the bigger issues in the states,” he wrote.

Other startups claim the proposed legislation is confusing. Until the Federal Aviation Administration provides clear guidance, “states will continue to set laws that will inevitably conflict with each other and will cause confusion about where and how operators can fly,” says Christian Sanz CEO of the San Francisco-based drone-maker Skycatch

Michael Drobac, executive director of the advocacy group Small UAV Coalition, makes a similar point: The bill seeks to regulate an industry that is still being defined with drone companies and operators still working under FAA exemptions rather than federal drone laws. 

Startups also argue that California could establish itself as the worldwide leader in drone innovation--if it weren't for the legal issues. 

“Do you think Google would have brought its drones to Australia for Project Wing if we had prohibitive regulations?” Matthew Sweeny, CEO of Australian drone startup Flirtey says. “Unreasonable regulations will stifle innovation.”

He suggested that California legislators look at what he described as a worldwide trend toward more liberal drone regulations.

“How ironic would it be if Silicon Valley, the birthplace of new technology, were the last place where people can receive drone deliveries?” he asked.

What's next.

Small UAV Coalition, which advocates on behalf of drone giants such as Amazon and Google as well as startups including DroneDeploy and Flirtey, plans to urge California Gov. Jerry Brown to veto the bill if it passes in the state legislature and makes it to the governor’s desk. Drobac says SB 142 would virtually prohibit commercial drone use in the state rather than manage the growing industry.

“It’s not just that it would hurt it or slow it down. I think it would ultimately stop it all together”--in California, that is--says Drobac. Of the coalition’s 17 members, 11 are based in California.

“I think some of them would move if California’s hostile enough,” he adds.

The coalition sent a letter dated Aug. 14 to bill sponsor Sen. Hannah-Beth Jackson with Gov. Brown CC’d and plans to send the governor a letter urging his veto early next week.

In addition to the coalition, the Association for Unmanned Vehicle Systems International and the Consumer Electronics Association have voiced their opposition to the bill. The organization’s presidents, Brian Wynne and Gary Shapiro, said in a statement released Thursday that the bill is “an unnecessary, innovation-stifling and job-killing proposal.”

Brown has vetoed restrictions on drone use in the past. A year ago, he vetoed a bill that would have required law enforcement agencies to acquire warrants for use of drones in situations other than emergencies like fires or hostage situations.

"There are undoubtedly circumstances where a warrant is appropriate. The bill's exceptions, however, appear to be too narrow," Reuters reported Brown as saying in his veto message.