The former Sun editor, who more recently was chief executive and chairman of radio company The Wireless Group, was confirmed in a stock market announcement on Friday as the purchaser of a 6% stake in Highbury.
According to the Sunday Times, he has upped this to 14.75%, which would mean he has put around £1.3m into Highbury. The company has not made a comment on his move.
Were MacKenzie to want the chief executive position, he would need to overturn the succession plan agreed by the Highbury board only last week. The incumbent Mark Simpson is to become deputy chairman on September 30, making way for Mike Frey, currently managing director of Highbury Entertainment.
The plan also involves chief operating officer David Nizol and group finance director Owen Davies leaving the company. Highbury is in a state of flux in the aftermath of the aborted friendly takeover by Future earlier this year, and has sold off or closed more than 40 of its magazines.
Among the titles closed were home interest titles Home and Inspirations, while Real Homes was sold off to Hachette Filapacchi.
Now valued at £8m and with around £30m of debt, it still owns lads' monthly Front, Practical Woodwork and a number of lower-profile leisure and special interest titles.
As a magazine publisher, Highbury is an unexpected choice for MacKenzie's next media adventure. However, he has moved between media during his career, going to L!ve TV after leaving The Sun in 1994 and then moving into the radio industry in 1999.
He had to divert from his intended radio plan earlier this year when he was forced out of The Wireless Group after a failed bid to secure control of the company's shares by teaming up with venture capitalists.
After Irish media company Ulster Television triumphed in May with a £98.2m bid more to shareholders' liking, MacKenzie left with a sum believed to be in excess of £7m for his 6.4% stake and his severance package.
However, MacKenzie is not necessarily finished with radio, having been reported to be preparing a bid for a radio licence in the North East, which is due to be advertised later this year.
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