Commissioner Larry Scott said the presidents and chancellors of the conference schools decided it would be in the best interest of the universities, athletes and fans to keep the status quo.
"While we have great respect for all of the institutions that have contacted us, and certain expansion proposals were financially attractive, we have a strong conference structure and culture of equality that we are committed to preserve," Scott said in a written statement.
Scott said the conference would focus instead on its own plans to launch "innovative television networks" and its current TV agreements.
The Pac-12 just this season expanded past its longtime roster of 10 schools by adding Colorado and Utah.
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