Ryder and Sennett reportedly revealed their news to guests at the Valentino show, which marked the end of Paris Fashion Week in France, on Thursday--before most of the world even knew they were dating.
But Ryder's spokeswoman, Mara Buxbaum, has denied the engagement story.
She tells WENN, "It's not accurate. They're dating and they have been dating for some time, but they're not engaged."
Ryder and Rilo Kiley guitarist Sennett met on the set of new movie Water Pill.
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