Companies need to look beyond labels such as gay or lesbian and embrace the whole spectrum of sexuality and gender identity to be truly inclusive in their workforce, the founder of the world's largest app for gay women said on Thursday.

More than half of the world's countries do not protect lesbian, gay, bisexual and transgender people against workplace discrimination.

But a growing body of research indicates this has a negative economic impact and limits companies' ability to attract staff, in particular young people, according to Robyn Exton, founder of HER, who recently spoke at aconference on gay rights in the workplace.

"A lot of companies have woken up to this but there is still a long way to go be fully inclusive and accepting of all the different gender identities and sexual orientations."

"It has become clear that millennials (those born between 1980 and 2000) want to work for companies that are inclusive," Exton, whose app has more than two million users in 55 countries, told the Thomson Reuters Foundation.

"A lot of companies have woken up to this but there is still a long way to go be fully inclusive and accepting of all the different gender identities and sexual orientations."

HER, which bills itself as the "best app for lesbian, bisexual and queer people worldwide", offers users the choice of more than 30 sexual orientations and gender identities.

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Among them are fluid, pansexual, polysexual, flexisexual, asexual, bigender, cis female as well as lesbian, queer, gay, bisexual and transgender.

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Exton said it is encouraging that companies are implementing gender neutral bathrooms or anti-gay harassment policies but progress on inclusion meant more than that.

"If it's just a tick-box exercise, millennials are acutely aware of that and won't buy it," said Exton. "That's why strong, authentic leadership on these issues is crucial for companies."

Exton said a powerful message could be to use queer storylines in advertising as this can reach a large audience.

Lloyds Banking Group, named this year as Britain's best employer for LGBTQ people in a survey by gay rights group Stonewall, featured a same-sex marriage proposal in its advertising.

It was also commended for becoming the first UK-owned company to extend a private health care policy to transgender people.

The Pride and Prejudice conference, that took place in London, New York and Hong Kong on Thursday, heard that becoming more inclusive is crucial for companies as by 2020 almost half the global workforce will be made up of millennials.

At the same time, large numbers of people from Generation Z, born from the mid-1990s to 2010, will be starting their careers.

A 2015 report by consulting firm Out Now estimated the U.S. economy could add an extra $9 billion a year if companies improved their ability to retain LGBTQ talent.

Studies indicated that countries where such policies do not exist are missing out, with the World Bank estimating India loses $31 billion a year in economic output because of widespread discrimination against LGBTQ people.

Despite company leaders becoming more vocal about inclusion of sexual minorities, their message is not getting through to more junior managers, a survey published this week by the Economist Intelligence Unit found.

The survey of 1,000 executives in 82 countries found 40 percent of junior staff said they did not know who guides company thinking on LGBTQ diversity and inclusion, while only 16 percent of top managers said they did not know.

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