E-book subscription services Oyster and Scribd have added another big five publisher, announcing they both are adding 1,000 titles from Macmillan. Oyster now claims to offer over 1 million titles; Scribd claims more than 500,000, and both say the number of frontlist titles on their lists is growing.

Macmillan joins Simon & Schuster and HarperCollins in offering titles through Oyster and Scribd as both services added such Macmillan authors as Ursula K. LeGuin, Mario Vargas Llosa, Michel Foucault, and Orson Scott Card.

However, the growth in frontlist e-books—books less than a year old— offered via subscription may be the most surprising new development. Offering frontlist titles would seem to offer the possibility of undermining the sales of hardcover editions of the same books. Most titles offered by these services continue to be backlist, and publishers—among them S&S and HarperCollins—have cited the utility of e-book subscription as a discoverability tools.

While Oyster's Eric Stromberg also cited backlist discoverability—he pointed to the Oyster Review, a newly launched online literary journal that doubles as a recommendation platform—he also said “20% of the books read on Oyster are new releases.” Randall Monroe’s What If? (Houghton) and The Storied Life of A. J. Fikry by Gabrielle Zevin (Algonquin), both available on Oyster, are both recent bestsellers.

Stromberg said, “it makes sense for publishers to offer new releases—it increases sales.” He said such publishers as Grove Atlantic, Houghton Mifflin, Melville House, Seven Stories Press and Other Press are among houses offering titles less than a year old through Oyster. “Only a small number of books get promotion. Through our recommendations we can find readers for underpromoted books,” Stromberg said.

While Macmillan is only offering backlist, Scribd spokespeson Lyndsey Besser also emphasized that frontlist titles—books six months old to a year—including audiobooks, are available on Scribd. “Timeframes certainly vary by publisher, some are 6 months, some are a year,” she said. “HarperCollins has given us frontlist—we experimented with Juliet Macur’s Cycle of Lies last year. Audiobooks are another area where we’re able to differentiate ourselves and get the newest content. Amy Poehler’s new book Yes Please, for example; we got the audiobook the day the print version was released.”

At one time literary agents expressed concerns that publishers may not have the right to offer titles via subscription. Now those concerns seem to have been diminished as more authors and titles are available via subscription. Oyster’s Stromberg credited the e-book subscription model, which pays publishers the full price of the book once a certain percentage of it has been read. “We developed this model with authors, agents and publishers from the beginning,” he said. “We just haven’t heard any objections.”

Besser agreed, noting that publishers and agents, “in general, are open to and excited about the opportunity,” to have books on Scribd. “At the end of the day Scribd is triggering more reads which results in more payouts. We quickly become a top revenue source for many authors.”