NEW YORK: The family heirs to Rupert Murdoch's News Corporation empire are set for the mother of all power battles when the clan patriarch finally quits the family business – feet first or otherwise – predicts the media mogul's biographer Michael Wolff.

By amazing coincidence, Wolff's headline-grabbing prediction coincides with the publication tomorrow (Tuesday) of his book The Man Who Owns the News – a move unlikely to injure the tome's sales. 

According to Wolff, an agreement (under which all six Murdoch scions enjoy equal economic rights  when the spoils of the clan's 38% controlling stake in NewsCorp are divided) also contains a codicil that restricts voting control to the eldest four 'children'.

But, claims Wolff, the 77-year-old mogul confided to him that the two children born to his third wife Wendi (née Deng) could share voting rights "when they are 25 or 30 or something".

A statement firmly rebutted by Murdoch's older offspring and the clan's lawyer. They are adamant that there is no such plan to renegotiate the trust that manages the NewsCorp stake.

Blabbed 'a person close to the family' to the Financial Times: "This is not a family that believes it needs legal deadlock provisions. They have always been very happy to rely on old-fashioned talking, arguing, shouting, threatening and ultimately compromise to reach consensus."

Conscious, no doubt, that a sprinkling of controversy always spices the sales recipe, Wolff's opus go on to stir speculation about the next occupant of NewsCorp's chair – theoretically vacant since his eldest son Lachlan quit all executive duties in 2005 to pursue other business opportunities.

Meantime, heir-presumptive James now runs NewsCorp's European and Asian operations after a successful spell at the helm of BSkyB, the clan's UK satellite monopoly.

Another tempting titbit from the tome illustrates the surgical  precision with which Murdoch père prepares his predatory strikes.

Wolff reports that prior to going public with his bid for Dow Jones, the magnate pored for many hours over the inner alliances and infighting among members of Dow's controlling Bancroft tribe.

He also gained insights into the embattled Bancrofts from Andrew Steginsky, who at the time ran an investment company in Princeton, New Jersey and enjoyed close relationships with two Bancroft heirs. This feedback prompted Murdoch not to sweeten his successful $60-a-share bid by an additional $1-$2. 

In this as in many other of his takeover triumphs, Murdoch followed the credo of Waterloo victor, the Duke of Wellington: "All the business of war, and indeed all the business of life, is to endeavour to find out what you don't know by what you do; that's what I called ‘guessing what was at the other side of the hill."

Data sourced from Financial Times; additional content by WARC staff