Casino operator Wynn Resorts has filed a lawsuit against rival Genting over the appearance of the latter’s in-development Las Vegas venue.

On the Friday before Christmas, Wynn’s legal grinches filed a lawsuit against Genting’s Nevada subsidiary Resorts World Las Vegas LLC, arguing that the unfinished Resorts World Las Vegas (RWLV) casino employs “a substantially similar architectural design” to Wynn’s existing Las Vegas casino properties.

Wynn’s filing argues that the shell of the $4b RWLV, which is going up just across the street from the Wynn Las Vegas and Encore buildings, already bears a striking resemblance to those properties, as well as to the Wynn Macau resort and the in-development Encore Boston Harbor casino in Massachusetts.

Those Wynn properties all feature a similar concave façade featuring distinctive curved bronze glass and cream-colored horizontal banding between the panes. The lawsuit alleges that RWLV’s design violates Wynn’s “copyrighted architectural work.”