Fairfax Media has embarked on the final stages of due diligence in a $30 million play for business journalism giant-killer Australian Independent Business Media (AIBM), as rumours of an imminent announcement snowball.

Crikey understands Fairfax has made a verbal offer of about $22.5 million for a 75% stake in AIBM -- which would value the company at $30 million -- and is currently combing over the online business' books, which includes the popular sites Business Spectator, Eureka Report, Climate Spectator and Technology Spectator.