The Seven Network has secured the free-to-air rights of the first seven seasons of The Big Bang Theory.
The deal effectively takes replays of the popular series off rival Nine, which has used them as high-value programming gap-fillers for the past several years..
Seven has confirmed it now holds the rights to the first 159 episodes of the series.
Seven will launch them on its main Seven channel, and the digital channel 7mate, in October.
Seven will take the rights to the show's eighth season in 2016.
Nine still retains the rights to new episodes of the series, including its upcoming ninth and subsequent seasons.
In broad terms, the acquisition of repeat rights would not normally be headline news, but Nine's relationship with The Big Bang Theory is different to that of most networks and most shows.
For the best part of its life, the series has been a high-performer for Nine.
In particular, repeats have delivered Nine high audience yields, prompting the network to use it frequently as gap-filler.
At the height of its popularity, in 2011, Nine 533 episodes of The Big Bang Theory across the ratings year; there were 260 plays on the main Nine channel and 273 plays on the digital channel Go.
Though its actual value would have softened slightly over time, replays still hold nine of the top 25 program slots on multi-channels for the first half of 2015, according to data from the ratings agency OzTam.
And episodes of The Big Bang Theory accounted for a total of 243 hours of programming on Nine in 2014.
In 2015, Nine has already aired 150 hours of Big Bang Theory episodes, demonstrating it was either on track to best its 2014 record, or was hoping to deplete their long-term value by over-scheduling them.
Seven's head of programming Angus Ross said the deal provided "demographic certainty" for Seven, acknowledging the series' value in reaching a younger segment of the audience.
"It will ensure we have Australia's biggest digital channels and will give 7mate unprecedented demographic dominance," Mr Ross said.
The rights for the series have been effectively on the market since Nine dissolved the bulk of its output agreement with the US studio Warner Bros.
The deal, which was worth roughly $100 million per year across its five year lifetime, was a huge cost burden on Nine.
Nine's relationship with Warner Bros, and the exclusive output deal which symbolised it, was created in the 1990s, at the height of the popularity of Warner hits such as Friends and ER.
Though the price tag for the deal went up, the studio never subsequently delivered a pairing like Friends and ER to Nine.
And the value of the deal was again brought into question as other historically strong titles, such as The Mentalist and Cold Case, played out.
The new arrangement creates an unusual situation where the rights to the series are split across two networks.
The last time Seven and Nine were forced to share a series, as it were, was when Seven owned the first season of Friends and Nine the second and subsequent seasons.
At the time, Seven delayed airing the first season to keep what was widely perceived to be a kingmaker at bay; in the end Seven and Nine launched the first and second seasons almost simultaneously.
The Seven-Warner Bros deal is not a studio output deal in the historic sense. It is understood that Seven and Warner Bros have contracted for a selection of titles from the Warner library.
