Rothy’s Inc. may proceed with a patent infringement suit alleging a competitor’s ballet flats are too similar to its shoes, a federal court said Dec. 20.

The complaint is sparse on details but filled out enough to survive a motion to dismiss, Judge Michael F. Urbanski wrote for the U.S. District Court for the Western District of Virginia.

Rothy’s has generated more than $40 million in revenue from its shoe, The Flat, since it launched it three years ago.

It sued JKM Technologies LLC, which makes a competing flat called the OESH Dream Flat.

JKM sought dismissal of the Lanham...