Last year, real estate tech companies landed $1.5B in funding, a big cash infusion into the sector. And the cash is coming from an interesting variety of sources, from the Milsteins and the Rudins to the LeFraks—all big real estate names.

Zachary Aarons, an angel investor and co-founder of MetaProp, says families have started to ask "Why am I just a customer?" Zach told The Real Deal about the families' interest in tech. “That’s a major tectonic shift that’s going to accelerate.”

Some families have put cash into tech directly related to their businesses. The LeFraks invested in Compass, a residential brokerage platform. The Rudin family is a backer of WeWork and leasing management software Hightower.

Developers are getting skin in the game, as well. Silverstein Properties is behind SilverTech Ventures, an accelerator that houses (at 7 World Trade Center, no less) and mentors new startups in exchange for a "single-digit" piece of the business. [TRD]