FRANKFURT/MUNICH (Reuters) – German portaloo firm Adco, known for its Dixi and Toi Toi brands, is up for sale with four private equity groups in the last round of bidding for the 700-800 million euro (624 million pounds) firm, people close to the matter said.

EQT, Triton, Apax and Core Equity Holdings are expected to submit binding offers by a July 10 deadline for the family-owned company with sales of 360 million euros, they added.

The company was formed by a merger of the two portable toilet brands Dixi and Toi Toi in 1997 and was run by Toi Toi founder Harald Georg Mueller until his death in 2014.

His wife and son took over but they opted to put the firm up for sale so a new owner could inject cash to fund the expansion of the fast-growing group and to put a stronger focus on value maximisation.

Citi has been mandated as sell side advisors, they said.

The bidders and Citi declined to comment, while a spokeswoman for Adco said she could not comment on a potential sale of the company.

Adco is expected to generate earnings before interest, tax, depreciation and amortisation of about 100 million euros this year and may be valued at 7-8 times that, one of the sources said.

Adco has had some operational issues of late, another of the sources said, adding that this was highlighted earlier this month when visitors of the Nuremberg Rock im Park festival complained about a lack of sufficient Dixi toilets.

In a sign that Adco’s expansion has hit a snag the company has exited certain European markets, the source added.

Adco ceased doing business in France, an Adco spokeswoman said, declining to elaborate the reasons for the move or when it happened.

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