Spines Lands $64M to Put AI Agents Behind Your Next Book

The cash comes in two pieces. Zeev Ventures led a $29 million Series A-1 equity round, with Aleph, NordStar, M-Fund, LionTree and angel investor Dan Senor joining in. Credit firm Twelve is providing another $35 million that Spines calls a non-dilutive growth financing facility. Spines declined to say what the round values the company at.

The money follows a growth spurt. Spines says its new AI-powered services pushed it to a $50 million annual revenue run rate, a 400% jump from a year earlier. Founder and CEO Yehuda Niv told Fortune the company has published more than 8,000 authors and roughly 12,000 titles, with about 400 new writers signing up every month.

Spines pitches itself as an operating system for authors. Writers upload a finished manuscript and specialized agents handle editing, proofreading, formatting, cover design, metadata, ebook and print-on-demand files, plus distribution to more than 100 channels including Amazon, Barnes & Noble and Baker & Taylor. Authors can also generate an audiobook with a synthetic narrator or a clone of their own voice, and translate both the book and the audiobook. Spines offers seven target languages today and wants to hit 20 within six months.

The pitch is speed and service. Niv says AI agents cut the manuscript-to-shelf grind from the many months or years traditional publishing takes down to weeks. Packages start around $3,000 and top out at $20,000 for a premium tier covering three languages with audiobooks each; most authors land in the $5,000 to $7,000 middle. Spines recently bumped its royalty split so authors keep 80% of net royalties, up from 70%, and reports royalties monthly instead of the industry's twice-yearly or annual statements. Weekly and eventually real-time reporting are next.

Niv's path into publishing started with a bad experience of his own. About 15 years ago, partway through a master's in electronic engineering, he published a book and decided the process was broken. He bootstrapped Niv Publishing into what he calls Israel's largest publishing house, putting out roughly 1,200 titles a year, then founded Spines in 2021 after concluding AI would make traditional publishers irrelevant. He says Spines only publishes books written 100% by humans and uses software to screen out AI-generated manuscripts. On copyright, he argues that licensing the image tools behind AI-designed covers and passing that license to authors gives them broader rights than human illustrators typically do.

Spines has about 350 employees, though only 50 work in R&D; the rest focus on customer success and support. Niv said the company is in early talks with one of the Big Five U.S. publishers about a partnership that would put Spines' agents to work inside that house's services. The debt facility will fund growth, while the equity goes toward product and expansion into the U.K., Canada and Australia. Niv is targeting 200% to 300% annual growth. Most staff sit in Eastern Europe, the U.S. and Latin America, but R&D and management are based in Herzliya, Israel. Oren Zeev, founding partner of Zeev Ventures, said in a statement that Spines has all the ingredients to become the category leader in the next generation of publishing.