(Reuters) - Italian broadcaster Mediaset MS.MI and shareholder Vivendi VIV.PA were negotiating on Friday to find a way to end a three-year legal battle after all-night talks failed to produce a breakthrough, sources said.

FILE PHOTO: A woman walks pass by a sign of Vivendi at the main entrance of the entertainment-to-telecoms conglomerate headquarters in Paris, France, November 21, 2019. REUTERS/Gonzalo Fuentes

Following are twists and turns in their dispute.

April 2016 - Vivendi agrees to buy Mediaset’s pay-TV business, billed as a major step in billionaire businessman Vincent Bollore’s plan to build a southern European content and video-on-demand powerhouse. The two companies agree to take a 3.5% stake in each other as part of the deal.

July 2016 - Vivendi backs away from the original deal, proposing an alternative that would give it a bigger direct stake in the broadcaster than originally agreed.

Vivendi says the main reason for the change is the unreliability of Mediaset Premium’s annual financial forecasts over the 2016-2018 period.

The deal falls apart as Mediaset rejects the new proposal by Vivendi and announces legal action against the French group.

Dec. 2016

Vivendi builds up a 28.8% stake in Mediaset over the month in a moved condemned by the Italian broadcaster.

April 2017

An Italian regulator orders Vivendi, which is also the top shareholder in Telecom Italia TLIT.MI, to cut its stake in either the telecoms group or Mediaset within a year to comply with rules designed to prevent a concentration of power.

Oct. 2017

Police raid the Paris headquarters of Vivendi as part of an investigation into alleged market abuse involving its purchase of the Mediaset stake.

Vivendi says the raid is the result of an “unfounded and unjust complaint” by former Italian prime minister Silvio Berlusconi, whose holding company Fininvest is the top investor in Mediaset.

April 2018

Vivendi transfers 19.19 percent of its shareholding in Mediaset to a trust to comply with the April 2017 ruling by the Italian communications regulator.

The legal battle between the two companies continues on multiple fronts, including a 3 billion euro damage request by Mediaset over the failed pay-TV deal and repeated complaints by Vivendi about not being allowed to exercise its voting rights at Mediaset shareholder meetings.

Sept. 2019

Mediaset shareholders back a plan, unveiled in June, to create a pan-European media group under a new Dutch holding, fending off opposition from Vivendi.

Under the plan, both Mediaset and its Spanish unit will be merged into a Dutch company dubbed MediaForEurope (MFE).

Vivendi, which says the new structure tightens the grip of Fininvest on the group, challenges the plan in court both in Spain and Italy.

Nov. 2019

Mediaset raises its stake in German rival ProSiebensat.1 PSMGn.DE to 15.1% as it presses ahead with plans to create a pan-European TV platform.

Mediaset and Vivendi try and hammer out a deal to end their legal stand-off.