The Walt Disney Company systematically underpays women, according to a new class-action lawsuit that alleges “widespread” discrimination at one of the world’s largest media corporations.

The attorneys taking on Disney, with a complaint filed in California on Tuesday, said the company has routinely paid women less than men for the same work, describing the problem as an “egregious gender pay gap that appears to be engrained in Disney’s culture”.

The suit has hit Disney just as the company has completed its $71bn (£54bn) acquisition of 21st Century Fox. The case, filed on behalf of all women who work at the Walt Disney Studios branch of the company in California, also came just days after the corporation reported that in the UK, it has paid men 22% more on average than women.

“This is apparently a worldwide problem, and we’re going to tackle it in California,” the attorney Lori Andrus told the Guardian on Wednesday. “Women are treated as cheap labor … and women are fed up with it.”

Disney said in a statement, “The lawsuit is without merit and we will defend against it vigorously.”

The complaint comes from Andrus Anderson, a law firm with a history of bringing equal pay cases against major corporations. The suit included allegations by two longtime Disney employees.

LaRonda Rasmussen was hired in 2008 as a senior financial analyst and eventually moved into a product development manager position. In 2017, she told Disney HR she believed she was making less than men with the same or similar job duties and asked for an audit, the suit said. She was then making a $109,958 base salary, but six men with the same title allegedly had significantly higher salaries – receiving between $16,000 to nearly $40,000 more than she was.

A recently hired male manager, with less experience than Rasmussen, was paid more than $20,000 more than she was, according to the suit. Five months later, Disney HR told her the gap “was not due to gender” but gave her a $25,000 raise that it attributed to an evaluation of “market forces”, the complaint said.

But her pay disparity, in violation of California’s equal pay laws, has continued, her lawyers said. As of 2018, she said she makes $5,270 less than the average salary of male managers. She makes roughly $34,000 less than male “senior” managers, who do similar work, she alleged. Rasmussen has also “always” received positive performance reviews.

The other named plaintiff, Karen Moore, is a senior copyright administrator within Disney Music Group and has worked at the corporation for 23 years. The suit said she was discouraged from applying for an open manager position, which the company then converted to a “senior” role and gave to a man, who makes significantly more than her despite them doing equivalent work.

“It was devastating,” Andrus said, describing Rasmussen’s discovery that she was paid less than male counterparts. “You can imagine how humiliating it is, especially … when your contribution is significant and longstanding. It’s just insulting to find out the guy who just graduated college a few years ago is making substantially more.”

Andrus added, “She was hopeful Disney would do the right thing and correct it immediately and completely.”

Given the size and reach of the company, which distributes films under Walt Disney Pictures, Pixar, Marvel, Lucasfilm and Touchstone, the case could have far-reaching implications, the lawyer said: “It is unimaginably influential in the corporate sector.”

Moore and Rasmussen are both women of color, and although the case does not allege racial disparities in pay, studies have consistently shown that the pay gap across industries is worse for minority women.

After publication of this article, Disney sent a statement late Wednesday saying the corporation had “robust pay equity practices and policies” supported by a “specialized team of Compensation professionals and lawyers”.

“As to the individual claims, we are confident that they will be found to be meritless when tested against the evidence, rather than the rhetoric of the complaint,” the statement added.

The suit comes amid a reckoning in Hollywood, media and other industries regarding pay discrimination, bolstered by the Time’s Up movement. In Silicon Valley, major corporations like Google and Oracle have faced similar litigation.

In Disney’s recent pay gap report in the UK, where companies are required to disclose this kind of analysis, the firm said it “takes a holistic approach to addressing and ensuring gender equality in our workforce”, adding, “We are proud of the percentage of women we employ across the organisation and that we compensate and promote people based on their roles, experience and performance.”

In recent years, Disney has also faced scrutiny over its pay of low-wage workers at the Disneyland resort in California.