Private equity firm Apax Partners, which has been a long time investor in spoken word digital audio firm Audible, (NSDQ: ADBL) is in the process of selling off its stake through a public offering, according to an SEC filing. Apax and its affiliated funds are divesting more than 23 percent of Audible’s public shares (about 5.9 million shares) that it has held till now.

Not sure what this means for the company, but it has been languishing from a low profile for a long time, and of course its share price slump…it certainly needs a transformative event sometime soon. Would a strategic buyer swoop for this chunk of shares? More in the SEC filing.

Disclaimer: Our investor Alan Patricof served as one of Audible’s directors from August 2003 until his resignation in June 2007.