Time Warner’s HBO unit has discontinued DVD sales to Netflix. While the move doesn’t prevent Netflix from supplying its customers with discs containing HBO content, it’s a symbolic gesture signaling that HBO content is meant to be, at least theoretically, exclusive, and that HBO considers Netflix a competitor that does not deserve favorable treatment.

As reported by The Hollywood Reporter, the change started January 1, so that instead of HBO selling discs of The Sopranos, True Blood, Deadwood — and everything else HBO has offered its subscribers — on the cheap to Netflix, the DVD-by-mail service must go elsewhere for them. Due to the First Sale Doctrine, Netflix can purchase discs at retail, if it likes, and rent them to its customers.

While HBO makes its content available to outsiders such as iTunes for rent on a per-episode basis, it does not want its content easily accessible in another subscription model, like Netflix, THR reports.

Netflix also has begun to encroach on HBO’s turf by delving into original content, such as Hemlock Grove, Lilyhammer and House of Cards.