A Walmart employee who married her wife before the company changed its policy to extend health insurance benefits to same-sex couples is now suing the retail giant, claiming it violated gender discrimination laws.

The lawsuit filed in U.S. District Court in Boston is seeking nationwide class-action status, reports Reuters. In it, an office manager who has worked at Walmart stores in both Maine and Massachusetts since 1999 says that her wife (who also worked for Walmart until 2008) developed cancer in 2012, and Walmart’s denial of insurance racked up $150,000 in medical debt for the couple.

The two women were married in Massachusetts in 2004, when the state became the first in the country to allow same-sex marriage. The lawsuit says the company repeatedly denied requests by the employee to add her wife to her insurance policy.

When she took her claims to the U.S. Equal Employment Opportunity Commission, Wal-Mart said federal anti-discrimination laws didn’t apply to lesbian, gay, bisexual and transgender employees, so it wasn’t required to offer benefits to their spouses.

The lawsuit says that past policy is a form of gender discrimination, as the wife of a male employee would’ve received health insurance.

In 2014, Walmart changed its policy and began offering health insurance benefits to same-sex spouses. Despite that, the lawsuit claims that workers can’t rely on the company to provide health insurance.

“Benefits provided by Wal-Mart as a matter of grace… are not secure and could potentially be withdrawn just when large health care costs are incurred,” the lawsuit says.

Consumerist asked Walmart for comment, as well as whether current employees can count on benefits for same-sex couples, and received the below statement from a spokesman:

“Walmart expanded its benefits starting in January 2014 and currently covers same sex spouses and domestic partners. We have not yet seen the details of the lawsuit and out of respect for [the plaintiff] we are not going to comment other than to say our benefits coverage previous to the 2014 update was consistent with the law.”

Wal-Mart sued over denying health insurance to gay worker’s wife [Reuters]

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