L-R: Co-founders of The Fourth Floor, Aparna Srinivasan, Breen Sullivan and Sarah Feingold.

When the founders of The Fourth Floor, a new initiative connecting women in-house counsel with business experience to female entrepreneurs, began spreading their idea late last year, they expected some interest, mostly from people in their network.

But their idea spread faster and farther than planned. The three co-founders began receiving hundreds of messages from interested women professionals and sponsors, with more than 200 applicants from 10 U.S. cities and three countries.

“We had to take a step back because we were moving full steam ahead, just, 'Yeah, we have this idea.' But we received so much interest … we need to do this really thoughtfully and carefully,” said Sarah Feingold, the co-founder of The Fourth Floor who has served as general counsel of Vroom and senior counsel at Etsy. At a dinner event for women founders, she said the initiative was so popular they “ran out of business cards.”

The massive outpouring of support is, in part, what co-founder and Watermark Insights' top lawyer Breen Sullivan said pushed the initiative from “just being a thought” to a “tangible” community. The Fourth Floor officially launches next week with a May 13 event at Davis Wright & Tremaine's New York office.

While support for the initiative came seemingly overnight, it took time and planning to transform what Sullivan called “an impulse” into an organization ready to run. She, Feingold and third co-founder Aparna Srinivasan, the chief executive officer and co-founder of SpotOn, held five focus groups with more than 40 women general counsel and entrepreneurs this year.

Again, Feingold was surprised by the initiative's support. For her first focus group, Feingold brought “snacks”—a small plate of falafel she assumed she'd be eating alone. But within minutes, she said, the room filled up with women professionals ready to brainstorm.

The focus groups built relationships: corporate counsel and entrepreneurs met women like themselves seeking community. But it also helped The Fourth Floor's co-founders tweak their initial plans on how in-house counsel and startup founders would be paired. Feingold said the group had planned to hold “speed dating” sessions to pair counsel with startups.

“We felt like it was it too matchmaker. And there's that weird thing of chemistry,” Feingold said. “We don't want to force any founder to put someone we chose on their board, because it's a really important and deep role for your company, and it's a long-term commitment.”

Now, she said, group members will meet at curated in-person events where they can make more natural connections. Sullivan said inaugural cohorts will have around 20 women each.

Focus groups also showed The Fourth Floor co-founders that different participants sought different benefits from the initiative.

Women “industry leaders”—lawyers who have made it to their company's C-suite—may act as angel investors, while non-C-suite in-house counsel with at least eight years experience will work closely with entrepreneurs to give business advice from their experience working at companies.

For non-chief legal officers with hopes of sitting in the top lawyer spot, it's a chance to gain business credibility and a possible seat on the startup's board. And startups get input from legal business professionals with strategies to help guide the company.

“Understanding that connecting these two groups together, where now the lawyers … [get] an opportunity to serve as a strategic adviser for a startup, the value proposition for the lawyer is quite clear,” Sullivan said. “Because this is something we all want. This experience.”

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New Initiative Aims to Connect Female In-Housers With Women Startup Founders