SYDNEY--TPG Inc. is the sole bidder for the DTZ property services unit of Australian engineering company UGL Ltd. (UGL.AU) after a deadline for final offers passed, a person familiar with the matter said Monday.

The U.S. private equity firm was the only company to make a fully financed bid from a shortlist of four interested parties, the person said.

UGL Chief Executive Richard Leupen said May 9 that the company was seeking offers well above 1 billion Australian dollars (US$937 million), but would likely proceed with a demerger of the business if bidders didn't meet its price tag.

On Monday, the Australian Financial Review newspaper reported that TPG made a fully financed offer, while the other three short-listed parties could only offer letters of interest. The interested parties are thought to have valued DTZ at between A$1.0 billion and A$1.2 billion, lower than UGL's hope for offers exceeding A$1.2 billion, the report said.

Write to Ross Kelly at ross.kelly@wsj.com

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