UPDATE 1-Freenet invites offers for webhosting unit Strato

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FRANKFURT, July 6 (Reuters) - German phone group freenet FNTG.DE has asked interested parties to make offers for its webhosting business Strato, the company said on Monday.

The Hamburg-based company gave no further details.

A source close to the sales process had told Reuters on June 5 freenet was looking to divest the unit and hoped to fetch 300 million to 400 million euros ($559 million).

The division has a staff of around 500.

Freenet shares were down 3.7 percent at 7.1 euros by 1029 GMT, underperforming the German technology index .TECDAX, which was down 1.2 percent.

Freenet recently sold its DSL business for 123 million euros to Internet service provider United Internet (UTDI.DE).

Freenet became Germany's third-largest mobile phone operator after taking over Debitel for 1.63 billion euros in April 2008, in line with its strategy to focus on its mobile business. (Reporting by Nicola Leske; Editing by David Holmes)