According to the Huffington Post, Philip Roth told a French magazine in an interview:

I do not intend to write for the next ten years. To tell you the truth, I'm done. Nemesis will be my last book. Look at E.M. Forster, he stopped writing fiction aged 40.

For quite a while there, it seemed that every new year brought a new Philip Roth book. Not all of them were great—I never got the appeal of Everyman, which I thought would've been an okay short story but felt awkward as a novel—but they were all at least interesting. A lot of writers come back from their retirement (Vonnegut published a few books after he claimed to be done the last time) but Roth says he hasn't written in three years. That seems pretty final to me.