Shares of AT&T and Time Warner shot up after a judge's decision to allow the telco's proposed $85 billion takeover of the media conglomerate to proceed.

AT&T's stock fell 2.5% (T) and Time Warner (TWX) shares were up as much as 4.8% in after-hours trading Tuesday.

The ruling from U.S. District Court Judge Richard Leon approving the AT&T-Time Warner deal, with no conditions attached, has broader implications across the U.S. media sector, as a favorable decision is viewed as a green light for other major M&A moves -- and several scenarios are already in play.

Disney's $52.4 bid for major pieces of 21st Century Fox is pending a vote by Fox shareholders. But Comcast has said it's prepped to top Disney's bid for the 21CF assets -- and it's widely expected that Comcast would pull the trigger if the AT&T-Time Warner merger got the go-ahead. Meanwhile, both Comcast and 21st Century Fox also are vying for U.K. satellite operator Sky.

Fox shares rose 4.6% in after-hours trading Tuesday, while Comcast fell 4% and Disney dropped 2%.

Ahead of the decision in the case, AT&T stock closed up 0.5% (to $34.50 per share) and Time Warner closed up 0.05% in regular trading (to $96.22 per share) which concluded at 4 p.m. ET.

Under AT&T's original deal for Time Warner, announced back in October 2016, the telco offered $107.50 per share for the media company ($53.75 per share in cash and $53.75 per share in AT&T stock). But because of a collar based on the average price of AT&T's stock at closing, the deal is worth around $103 per share to Time Warner shareholders.

The antitrust case was brought by the Justice Department, which had argued AT&T's ownership of Time Warner would put the telco in a position to raise programming prices for rivals.