CALIFORNIA: Investing in a social network closely tied to a booming industry sounds great, until Apple kicks the thing you invested in out of the App Store because the platform is all about marijuana.

It’s one of the many things that can happen when two of the fastest growing industries in America come together, as is taking place this week in San Francisco, where several dozen entrepreneurs are pitching 200 or so investors, Shark Tank style.

Organizers of the investor-pitch forum cite as legitimacy the recent multimillion dollar investment by Silicon Valley titan Peter Thiel‘s Founders Fund in a holding company of several marijuana-related firms. The entrepreneurs at the Fairmont Hotel are pitching startups selling marijuana-growing equipment, apps that help with medicinal marijuana delivery, and even a spray that an entrepreneur says was developed at the Lawrence Livermore National Laboratory that coats marijuana with grower information, acting as a kind of DNA bar code.

“It’s more suited to what cannabis would be in the future,” says DNA Trek founder Anthony Zografos.

Since Colorado and Washington first voted to legalize recreational marijuana use in late 2012, the legal cannabis market has grown from $1.5 billion in 2013 to $2.7 billion last year, according to industry estimates. That kind of velocity gets the attention of investors, many of whom focus on tech.