Foreigners who were once considered solid candidates for an H-1B visa — those with multiple degrees, high salaries offered by major tech companies and, in at least one case, an actual rocket scientist — are receiving extra scrutiny and delays on their applications.

Thousands are also getting denied, prompting them to go home or revise their career plans.

More than twice as many H-1B applications were rejected in November compared with the same time last year, according to U.S. Citizenship and Immigration Services data provided to The Chronicle. The newly reported data show that the administration is acting on its promise to curtail a work program for foreigners that it says is rife with loopholes and abuse.

Immigration officials have ramped up their scrutiny of the visas through “requests for evidence,” documents that demand employers offer further proof of why the applicant deserves a visa.

According to the data, 17.6 percent of 30,445 completed H-1B applications — meaning they were reviewed by the government — were denied in November. This compares with 7.7 percent of 30,161 completed applications in November 2016. From August to September, the proportion of applications that received a request for evidence more than doubled to 37.9 percent, while the number of completed H-1Bs stayed nearly the same. By November, nearly half received the evidence requests.

“After the Trump team got settled in, the number of requests for evidence shot up dramatically and the approval rates for H-1Bs started to decline,” said Stuart Anderson, executive director of National Foundation for American Policy, a nonpartisan research organization, who reviewed the data provided to The Chronicle.

The immigration agency’s director, Lee Francis Cissna, said in a statement that the increase in requests for evidence “reflects our commitment to protecting the integrity of the immigration system.”

“We understand that (requests for evidence) can cause delays, but the added review and additional information gives us the assurance we are approving petitions correctly,” he said.

Even after immigration lawyers answer the requests — often with detailed explanations that can spill well over 100 pages — there seems to be no pattern for who is accepted and who is denied, say dozens of attorneys, employers and visa applicants.

Frida Yu, 34, is a Chinese citizen with a master’s in business from Stanford, two law degrees, and four years of work experience at a “top international firm” in Hong Kong. She planned to work for a Bay Area startup as a financial analyst. After being chosen in the lottery, she got a request for evidence in July.

Three months later: denied.

Hong-Kit Wong, 25, also from China, has a bachelor’s degree from Berkeley and two internships at major tech companies. Much to his surprise, he was accepted — unlike more than a dozen of his friends who he said weren’t as lucky.

“I don’t feel like I am any more qualified than them,” he said at a cafe on Mission Street across from the startup office where he now works in San Francisco. “It seems like I just got lucky.” Wong didn’t receive a request for evidence.

There are many reasons an application might be approved and another rejected, ranging from the proposed salary, the employer’s history and the applicant’s education level. H-1B visas are reserved for “specialty occupations,” which means a job that requires at least a bachelor’s degree.

But what’s new, experts say, is not only the volume of requests but also the nature of them: “We’re seeing denials on applications that we’ve gotten approved for the last 20 years,” said William Stock, former president of the American Immigration Lawyers Association.

Lawyers say they’ve had to justify why positions like a financial analyst or data scientist requires a college degree. Other requests repeat questions asked in the original application.

Ellen Krengel, an immigration attorney, was asked to justify a visa for a rocket scientist: “It’s frustrating when you have a case that before would have been a slam-dunk approval and then to get this type of query.” Her client ultimately got a visa.

Government data show that despite the higher denial rate, most applications get approved. Zendesk, the San Francisco software company, said all of its H-1B petitions that received requests for evidence this year were accepted, and immigration lawyers around the country report similar success.

On Thursday, the Trump administration published a list of legislative priorities for the coming year that included changing the definition of who qualifies for an H-1B visa.

But absent legislative action, those who wish to see changes in the program see the increase in requests for evidence as a sign that the administration is making good on its promise.

“One of the benefits of closing loopholes and removing bad actors is that more startups and tech companies will have a higher probability of winning the lottery system,” said Manan Mehta, a founding partner of Unshackled Ventures, a venture-capital firm that supports foreign-born entrepreneurs. Mehta says he values immigration but supports H-1B reforms.

But regardless of how many applications are getting approved, experts say the increased scrutiny is deterring companies and foreigners from using the program.

Dean Garfield, president and CEO of the Information Technology Industry Council, which represents major tech companies such as Facebook, Google and Apple, said his members are reconsidering their use of the program.

For multinational companies, he said, that might not mean hiring American; it might mean hiring overseas.

“The concern is that the H-1B process will be even more cumbersome than it already is,” Garfield said. “Companies will not fill roles that would otherwise contribute to the economy, or fill those roles outside of the U.S.”

Caught in the middle are applicants who had set their sights on working here.

Atul, an Indian citizen who works at a major Bay Area tech company and declined to provide his last name because his visa application is pending, said he cannot take on any long-term projects or travel overseas while he waits for an answer.

“I’ve been here 5½ years of my life,” he said. “And once it’s rejected, you don’t have much time. You suddenly have to leave.”

Trisha Thadani is a San Francisco Chronicle staff writer. Email: tthadani@sfchronicle.com Twitter: @TrishaThadani