As the Supreme Court heard arguments in March for the two gay marriage cases it decided last week, one image was shared again and again, adorning the Facebook and Twitter pages of brands, celebrities and political leaders: an equal sign in red, the color synonymous with love.

It was only fitting that the logo of the Human Rights Campaign would become the symbol of the two gay marriage wins at the Supreme Court last week – on California's same-sex marriage ban, and on federal benefits for gay couples. HRC, the largest LGBT group in the country, had thrown an enormous amount of resources behind the fight for gay marriage. Its "Millions for Marriage" campaign had, quite literally, raised millions.

But while the HRC has racked up win after win on marriage, it may be quietly losing another, harder battle, a battle some say it hasn't fought very hard to win: the fight against HIV/AIDS.

In December 2012, the Centers for Disease Control and Prevention released startling new data that showed HIV was still plaguing the gay community. While new HIV infections had remained steady in the general public between 2008 and 2010, infections had risen by an incredible 22 percent in young gay men. Gay men represented two-thirds of new infections. And nearly 6,000 gay men were dying of AIDS every year.

The Kaiser Health Foundation recently described the problem of HIV in the city of Washington, where the HRC and many other big LGBT groups are headquartered, as "as epidemic on par with some developing nations."

"Gay and bisexual men remain at the epicenter of the HIV/AIDS epidemic," says Jonathan Mermin, the director of the CDC's division of HIV/AIDS prevention. "But HIV is not always at the top of the list of priorities for LGBT organizations."

When HRC spokesman Michael Cole-Schwartz lists off the priorities for the organization, the list is long: gay marriage, workplace nondiscrimination protections, safe schools, corporate support and benefits for employees, fostering positive places of worship. He doesn't name HIV/AIDS.

Choosing priorities, Cole-Schwartz says, is a "balancing act" and the issue of HIV/AIDS is one he says "thankfully we haven't had to deal with too much." Most of HRC's work on the disease, he says, is done through partnerships or coalitions.

It's not just the HRC. HIV/AIDS isn't a top priority for any of the three major LGBT groups in the U.S.: not the HRC, or the Gay and Lesbian Alliance Against Defamation (GLAAD), or the National Gay and Lesbian Task Force (NGLTF) – who together are somewhat pejoratively known as "Gay Inc."

"'Gay Inc.' is interested in military, marriage, and money," says Michael Petrelis, a gay and AIDS activist, in reference to the campaigns against the military policy of "don't ask, don't tell," which was overturned in 2010, and the Defense of Marriage Act, which was ruled unconstitutional last week. "But for the millions of gay people who don't want to be soldiers, who don't want to get married, where's the advocacy?" he says.

Peter Staley, a gay activist who founded the Treatment Action Group, a HIV/AIDS activist organization, also uses the term.

"The recent rise of HIV/AIDS ... is huge and it's not talked about because 'Gay Inc.' says nothing about it," he says.

In a recent op-ed in The Washington Post, Staley urged 'Gay Inc.' to allocate 10 percent of its budget to fighting HIV. He estimates the groups currently spend less than 1 percent, a number HRC said it couldn't confirm or deny because it doesn't break down its spending by issue type, while GLAAD and NGLTF didn't respond to request for comment. (HRC's total budget is more than $40 million.)

Internal Revenue Tax forms for all three groups mention a number of policy focuses but make no mention of HIV/AIDS.

"When you have the largest gay group in the country doing small things that really are just tokenism, how can we argue to the country that the government should care?" Staley says.

It wasn't always this way. In the 1980s and the 1990s, when HIV hit its peak, the gay community was at the forefront of the fight against the silent killer. A group called ACT UP formed in New York with the motto "silence=death," and went on to hold highly publicized demonstrations, one of which successfully helped lower the price of a new AIDS drug. The group fought hard against the social stigma of HIV and demanded support, as well as new research and treatments.

"LGBT groups are great activists. We showed that at the beginning of the AIDS epidemic when the epidemic wasn't being taken seriously," says Chris Collins, head of public policy for the Foundation for AIDS Research, known as amfAR, a major global HIV/AIDS nonprofit. "We absolutely need LGBT groups to become more engaged again in the effort to fight AIDS in the United States."

In recent years, efforts to fight AIDS have moved abroad, while activism in the gay community at home has gone largely toward gay marriage.

According to a recent report from the Funders Concerned About Aids, the top funders fighting HIV – those who gave $300,000 or higher – fell by nearly 30 percent since 2005. That same year, a number of states took first steps toward affirming gay marriage.

"LGBT groups have simply been AWOL on HIV," says Mark Harrington, a gay activist who heads the Treatment Action Group. "They don't lobby in D.C. for funding. They don't take policy positions. And they don't advocate for more funding or research."

That's not entirely true: Cole-Schwartz says HRC is currently lobbying for the Early Treatment for HIV Act, which would allow states to provide Medicaid coverage for low-income people with HIV, and previously lobbied for the Ryan White Care Act, the largest federal program for people with HIV/AIDS.

But most lobbying is done by HRC partners, Cole-Schwartz says.

And Collins thinks that with a public health issue this pressing for the gay community, that level of involvement doesn't make sense.

"LGBT leadership has a critical role: it needs to do more to let gays and lesbians know how important it is to take care of their own health. To let them know the science, and the treatment," he says. "We've siloed out our efforts, and the big groups don't think they need to do anything because they think 'the HIV/AIDS group will do that.'"

Collins says it's not about 'Gay Inc.' spending more money on HIV, but about them integrating it into what they're already doing, such as talking about HIV when they talk about other problems for gay youth.

"We all have to come to grips about how interrelated this all is," he says.

According to the CDC, if HIV continues to spread at its current rates, more than half of college-aged gay men will have HIV by the age of 50.

There are small indications 'Gay Inc.' may get more involved in the HIV fight going forward. Mermin at the CDC says that when the new HIV incidence data came out, CDC held a teleconference with the big LGBT groups to discuss the problem. "Many organizations said they hadn't prioritized this over the last decade, and they said they were re-inspired," he says.

Last year, HRC also created – for the first time – a position for a director of a new health and aging program.

And Collins and Staley say they have plans to meet with the largest LGBT groups to talk about how to better integrate HIV work.

But Staley worries that the lack of attention to HIV may be generational.

"Gay marriage is the feel-good story for our age. It's a noble cause. It's about love," he says.

"We were so burnt about HIV/AIDS. The younger generation views that as something the older generation went through. And they are very resistant to having it define them."