"While this development is long overdue, inviting one group to march at the exclusion of all others ... is a far stretch from the full inclusion we deserve," Schaefer said.
Sarah Kate Ellis, president of the gay-rights group GLAAD, said parade organizers who announced other gay groups could apply for the parade in 2016 and afterward "must be held accountable" to that pledge.
"As an Irish-Catholic American, I look forward to a fully inclusive St. Patrick's Day Parade that I can share with my wife and children, just as my own parents shared with me," Ellis said.
The New York City Saint Patrick's Day Parade Committee said Wednesday that OUT(at)NBCUniversal, an LGBT resource group at the company that broadcasts the parade, would be marching up Manhattan's Fifth Avenue on March 17 under an identifying banner.
Parade Committee vice chairman John Lahey said the NBC group's application was the only one the committee had received from a gay group for next year's parade. He also said, "We don't encourage or discourage applications from other groups."
In the past, organizers said gays were free to march in the nation's biggest and oldest St. Patrick's Day Parade but only with other groups and not with banners identifying them as gay.
The exclusion had made participation in the march a political issue in recent years. The committee said it made the "gesture of goodwill to the LGBT community in our continuing effort to keep the parade above politics."
But gay leaders said the organizers were forced into it.
"They weren't nudged, they were shoved into making this decision," said Fred Sainz, a spokesman for the Human Rights Campaign. "They were increasingly beginning to look like dinosaurs.
"In one of the world's most diverse and inclusive cities, not to allow gay people to march was becoming an anachronistic decision that they could no longer reasonably justify."
The inclusion of OUT(at)NBCUniversal came in the midst of major triumphs for gays and supporters in court rulings on same-sex marriage. When a federal judge on Wednesday upheld Louisiana's ban on same-sex marriages, it was the first loss for gay-marriage supporters after more than 20 consecutive rulings overturning bans in other states.
And it came after Pope Francis set the stage for a radical shift in tone about Roman Catholic Church teaching on homosexuality when he said "Who am I to judge?" about the sexual orientation of priests.
Parade organizers said they were "remaining loyal to church teachings," and Cardinal Timothy Dolan, next year's grand marshal, said the committee had his "confidence and support."
"I have no trouble with the decision at all," he said.
The exclusion of gay groups prompted first-term Democratic Mayor Bill de Blasio to refuse to march in the 2014 parade, and Guinness and Heineken withdrew their sponsorships.
De Blasio said Wednesday that the inclusion of OUT(at)NBCUniversal was "a step forward," but he would not commit to next year's parade until he knows more.
Guinness' parent company said, "We are pleased to see that the various parties are making progress on this issue." It said it was open to talking with the organizers about supporting the 2015 parade.
NBC, whose local affiliate has been televising the parade since the 1990s, would not confirm reports that it had threatened to drop coverage over the issue of gay participation. But it said NBC executive Francis Comerford, a member of the parade committee, helped with the agreement to include OUT(at)NBCUniversal.
Whether it was the mayor or the pope or the people at Guinness who prompted the decision, gay groups took some satisfaction in their role even if it didn't produce everything they wanted.
"This was decades' worth of work," said Ellis, of GLAAD. "The LGBT organizations are the ones that put pressure on the corporations that were sponsoring the parade, and when they withdrew it was the straw that broke the camel's back."
Associated Press writers Shawn Pogatchnik in Dublin and Jonathan Lemire and Karen Matthews in New York and AP Television Writer David Bauder in New York contributed to this report.